Free Online Calculators
836+ calculators for finance, health, math, conversions, and everyday life. Fast, accurate, and completely free.
Mortgage Calculator Calculate your monthly mortgage payment including principal, interest, taxes, an
Loan Calculator Calculate monthly loan payments, total interest, and total cost for any personal
Compound Interest Calculator Calculate compound interest with monthly contributions. See how your money grows
Savings Calculator Calculate how much your savings will grow with regular monthly deposits. See you
Investment Calculator Calculate the future value of investments with monthly contributions. See how mu
Auto Loan Calculator Calculate your monthly car payment, total interest, and total cost for any auto
Retirement Calculator Calculate your retirement savings balance and estimated monthly income. See how
Salary Calculator Convert annual salary to hourly, daily, weekly, bi-weekly, and monthly pay. Inst
Paycheck Calculator Estimate your take-home pay after federal taxes, state taxes, FICA, and deductio
Tip Calculator Calculate tip amount and total bill instantly. Split the bill between multiple p
Amortization Calculator Calculate monthly loan payments and total interest for any amortizing loan. See
Interest Calculator Calculate compound interest earned on any principal amount. Compare simple vs co
Down Payment Calculator Calculate how much you need for a down payment on a home. See total cash needed
Debt Payoff Calculator Calculate how long it takes to pay off debt and total interest paid. See your de
Credit Card Payoff Calculator Calculate how long to pay off credit card debt and total interest cost. See the
Savings Goal Calculator Calculate how long it takes to reach your savings goal. Enter your target amount
Income Tax Calculator Estimate your 2024–2025 federal income tax using current tax brackets. See your
Sales Tax Calculator Calculate sales tax amount and total price with tax. Also reverse-calculate the
Inflation Calculator Calculate the future value of money adjusted for inflation. See how inflation er
Net Worth Calculator Calculate your net worth by adding up all assets and subtracting all liabilities
Budget Calculator Calculate your monthly budget surplus or deficit. Track income vs expenses acros
ROI Calculator Calculate return on investment (ROI) percentage, net profit, and annualized ROI
Simple Interest Calculator Calculate simple interest using the I = P × R × T formula. Find interest earned
Hourly to Salary Calculator Convert hourly wage to annual salary. Calculate yearly, monthly, bi-weekly, and
Rent vs Buy Calculator Compare the true cost of renting vs buying a home over your time horizon. Includ
Currency Converter Convert between USD, EUR, GBP, JPY, CAD, AUD, CHF, CNY, INR, MXN and more. Appro
House Affordability Calculator Find out how much house you can afford based on your income, debts, and down pay
Student Loan Calculator Calculate monthly student loan payments, total interest, and payoff timeline. Co
401(k) Calculator Project your 401(k) balance at retirement based on salary, contributions, employ
Refinance Calculator Calculate your monthly savings, break-even point, and total savings from refinan
CD Calculator (Certificate of Deposit) Calculate the maturity value and interest earned on a Certificate of Deposit. Co
Present Value Calculator Calculate the present value of a future sum, annuity, or growing annuity. Includ
Car Lease Calculator Calculate your monthly car lease payment using vehicle price, residual value, an
Closing Cost Calculator Estimate home buying closing costs including origination, appraisal, title, and
Annuity Calculator Calculate annuity payments from a lump sum investment. Find monthly income, tota
Tax Refund Calculator Estimate your 2026 federal tax refund or amount owed. Uses 2026 tax brackets and
Stock Profit Calculator Calculate stock trade profit or loss, ROI, and after-tax gains. Supports multipl
Estate Tax Calculator Estimate 2026 federal estate tax using the $7M exemption after the TCJA sunset.
Rental Property Calculator Calculate rental property cash flow, cap rate, and cash-on-cash return. Full exp
Pension Calculator Calculate your defined benefit pension amount using years of service, final sala
Tax Bracket Calculator Find your 2026 federal tax bracket, marginal rate, and effective rate instantly.
APR Calculator Calculate the true Annual Percentage Rate (APR) on any loan. See how origination
Roth IRA Calculator Calculate your Roth IRA balance at retirement with 2026 contribution limits ($7,
Payroll Tax Calculator Calculate employer payroll taxes including FICA (Social Security 6.2% + Medicare
Stock Average Calculator Calculate your weighted average stock price across multiple purchases. See total
Capital Gains Tax Calculator (2026) Calculate federal capital gains tax for stocks, crypto, and real estate. Include
Cost of Living Calculator — Compare Cities & Salaries Compare cost of living between cities and calculate the equivalent salary needed
Debt-to-Income (DTI) Ratio Calculator Calculate your debt-to-income ratio for mortgage qualification. Check front-end
Future Value Calculator — FV of Investments Calculate the future value of a lump sum or recurring investments with compound
Mortgage Points Calculator — Is Buying Points Worth It? Calculate the break-even period for buying mortgage discount points. Compare 0,
Cash Back Calculator — Maximize Credit Card Rewards Calculate how much cash back you earn per year by spending category. Compare fla
Moving Cost Calculator Estimate moving costs for local and long-distance moves. Compare DIY truck renta
Rent Affordability Calculator Calculate how much rent you can afford based on income, debt, and expenses using
CAGR Calculator Calculate compound annual growth rate (CAGR) from beginning and ending values. I
HELOC Calculator Calculate HELOC monthly payments during draw and repayment periods. Compare HELO
Dividend Calculator Calculate annual dividend income from stocks, ETFs, and REITs. Model DRIP reinve
Take-Home Pay Calculator Calculate your take-home pay after federal and state taxes, Social Security, Med
Emergency Fund Calculator Calculate your ideal emergency fund size based on monthly expenses and risk prof
Home Equity Calculator Calculate your home equity, loan-to-value ratio, and tappable equity. Project eq
Car Payment Calculator Calculate your monthly car payment, total interest, and out-the-door cost. Inclu
Personal Loan Calculator Calculate your personal loan monthly payment, total interest, and effective APR
Mortgage Payoff Calculator Calculate how much time and interest you save by making extra mortgage payments.
Property Tax Calculator Calculate annual and monthly property taxes by rate or assessment ratio. Compare
Social Security Calculator Estimate your Social Security monthly benefit using the 2026 PIA formula with be
Life Insurance Calculator Calculate how much life insurance coverage you need using income replacement, th
Boat Loan Calculator Calculate your monthly boat loan payment, total interest, and full cost of owner
College Savings Calculator Calculate how much to save for college using a 529 plan. Projects inflation-adju
Interest Rate Calculator Calculate the implied interest rate (APR) from a loan principal, monthly payment
Bond Yield Calculator Calculate bond current yield, yield to maturity (YTM), yield to call (YTC), Maca
RV Loan Calculator Calculate your monthly RV loan payment, total interest, and full cost of ownersh
FIRE Calculator Calculate your FIRE number, years to financial independence, and Coast FI target
Cap Rate Calculator Calculate capitalization rate for investment properties. Includes NOI from expen
Crypto Profit Calculator Calculate cryptocurrency profit, loss, and ROI. Includes DCA (dollar cost averag
Effective Annual Rate Calculator Convert nominal APR to EAR with daily, monthly, quarterly, semi-annual, and cont
Tax-Equivalent Yield Calculator Calculate the tax-equivalent yield of municipal bonds vs taxable bonds. Compare
Real Estate Commission Calculator Calculate real estate agent commission, listing vs buyer agent split, seller net
Lease vs Buy Calculator Compare the true cost of leasing vs. buying a vehicle or equipment. Includes tot
NPV Calculator Calculate Net Present Value (NPV), Internal Rate of Return (IRR), MIRR, and Prof
College Cost Calculator Estimate the total cost of college including tuition, room & board, books, and f
Mortgage Insurance (PMI) Calculator Calculate your monthly PMI cost, annual PMI expense, current LTV ratio, and when
Tax Withholding Calculator (W-4) Calculate your recommended W-4 withholding for 2026. Estimate federal income tax
IRR Calculator Calculate Internal Rate of Return (IRR) for equal or variable cash flows. Compar
Black-Scholes Options Pricing Calculator Calculate European call and put option prices using the Black-Scholes model. Inc
Option Greeks Calculator Calculate all 5 option Greeks: Delta, Gamma, Theta, Vega, and Rho for call and p
Implied Volatility Calculator Calculate implied volatility (IV) from a market option price using Newton-Raphso
Covered Call Calculator Calculate covered call P&L, maximum profit, breakeven price, and annualized retu
Iron Condor Calculator Calculate iron condor max profit, max loss, breakeven prices, and probability of
Forex Pip Calculator Calculate forex pip value in USD and total P&L for any currency pair and lot siz
Forex Position Size Calculator Calculate forex position size based on account balance, risk percentage, and sto
Margin Call Calculator Calculate when a margin call is triggered for stocks (Reg T), forex, and crypto.
Sharpe Ratio Calculator Calculate the Sharpe ratio to measure risk-adjusted portfolio performance. Compa
Sortino Ratio Calculator Calculate the Sortino ratio using downside deviation instead of total volatility
Beta Calculator Calculate stock beta (β) from return series or variance/covariance inputs. Inclu
CAPM Calculator Calculate expected return using the Capital Asset Pricing Model (CAPM): E(R) = R
WACC Calculator Calculate Weighted Average Cost of Capital (WACC) for DCF valuation. Includes 3-
Bond Duration Calculator Calculate Macaulay Duration and Modified Duration for bonds. Includes DV01 (doll
Bond Convexity Calculator Calculate bond convexity and estimate price changes for large yield moves using
Yield to Maturity Calculator Calculate precise Yield to Maturity (YTM) using Newton-Raphson bisection. Compar
DCF Calculator Calculate enterprise value using Discounted Cash Flow (DCF) analysis. Includes 5
Dividend Discount Model Calculator Calculate intrinsic stock value using the Dividend Discount Model (DDM). Include
Enterprise Value Calculator Calculate Enterprise Value (EV) from market cap, debt, cash, preferred stock, an
P/E Ratio Calculator Calculate Price-to-Earnings ratio, earnings yield, forward P/E, PEG ratio, Shill
Kelly Criterion Calculator Calculate the optimal Kelly fraction f* = (bp − q) / b for sports betting and in
HSA Calculator Calculate your HSA balance at retirement with 2026 contribution limits ($4,400 s
FSA Calculator Calculate FSA tax savings with 2026 limits: Healthcare FSA $3,300, Dependent Car
RMD Calculator Calculate your Required Minimum Distribution using 2026 IRS Uniform Lifetime Tab
Roth Conversion Calculator Calculate whether a Roth IRA conversion makes sense. Compare tax cost now vs fut
Inherited IRA Calculator Calculate required distributions for inherited IRAs under the SECURE Act 2019 10
Reverse Mortgage Calculator Calculate HECM reverse mortgage loan amounts, monthly payments, and line of cred
Mortgage Recast Calculator Calculate your new monthly mortgage payment after a recast. A lump-sum payment r
PITI Calculator Calculate your full monthly PITI mortgage payment with a detailed breakdown of P
Escrow Calculator Calculate your monthly mortgage escrow payment for property taxes and homeowners
Charitable Donation Tax Calculator Calculate the tax savings on charitable donations in 2026. Compare cash vs appre
Dollar-Cost Averaging Crypto Calculator Calculate the results of dollar-cost averaging into Bitcoin or crypto. Compare D
NFT ROI Calculator Calculate your net profit and ROI from buying and selling NFTs. Accounts for mar
Crypto Staking Calculator Calculate crypto staking rewards, APY compound growth, and after-tax returns. Su
Impermanent Loss Calculator Calculate impermanent loss for DeFi liquidity providers. Supports Uniswap V2 50/
Mining Profitability Calculator Calculate Bitcoin and GPU mining profitability. Input hash rate, electricity cos
Gas Fee Calculator Calculate Ethereum gas fees in ETH and USD. Supports EIP-1559 base fee + priorit
XIRR Calculator Calculate XIRR (Extended Internal Rate of Return) for investments with irregular
BMI Calculator Calculate your Body Mass Index (BMI) using weight and height. See your BMI categ
Calorie Calculator Calculate daily calorie needs based on age, gender, weight, height, and activity
Body Fat Calculator Calculate body fat percentage using the U.S. Navy method with waist, neck, and h
BMR Calculator Calculate your Basal Metabolic Rate using both Mifflin-St Jeor and Harris-Benedi
TDEE Calculator Calculate Total Daily Energy Expenditure based on BMR and activity level. Find y
Macro Calculator Calculate daily macronutrient targets — protein, carbs, and fat grams — based on
Ideal Weight Calculator Calculate your ideal body weight using Devine, Robinson, Miller, and Hamwi formu
Protein Calculator Calculate how much protein you need per day based on weight and fitness goals.
Pregnancy Calculator Calculate your due date, current trimester, and weeks pregnant based on your las
Due Date Calculator Calculate your baby's due date from last menstrual period or conception date. Se
Ovulation Calculator Calculate your ovulation date and fertile window based on your menstrual cycle l
Sleep Calculator Calculate optimal bedtimes based on your wake-up time and 90-minute sleep cycles
Water Intake Calculator Calculate how much water you should drink daily based on weight, activity level,
Heart Rate Calculator Calculate maximum heart rate and target training zones using the Karvonen method
Pace Calculator Calculate running or walking pace, speed, and predicted finish times from your d
Calories Burned Calculator Calculate calories burned during exercise based on activity type, duration, and
BAC Calculator Estimate blood alcohol content based on drinks consumed, body weight, gender, an
One Rep Max Calculator Estimate your one-rep max (1RM) from weight lifted and reps completed. See train
Height Calculator Predict a child's adult height using the mid-parental method. Enter parents' hei
Period Calculator Predict your next period date, fertile window, and ovulation day. Track cycle re
Blood Type Calculator Predict possible child blood types from parents using Punnett square genetics. C
Conception Calculator Estimate your conception date from your due date, actual birth date, or last men
Waist-to-Hip Ratio Calculator Calculate your waist-to-hip ratio (WHR) and assess cardiovascular and abdominal
Baby Growth Calculator Calculate your baby's weight and length percentiles by age using WHO/CDC growth
Pregnancy Weight Gain Calculator Calculate recommended pregnancy weight gain based on pre-pregnancy BMI using IOM
Body Surface Area Calculator Calculate body surface area (BSA) using Mosteller, DuBois, and Haycock formulas.
Cycling Calorie Calculator Calculate calories burned cycling based on weight, speed, duration, and terrain.
Keto Calculator Calculate your keto diet macros including daily calories, fat, protein, and net
Net Carbs Calculator Calculate net carbs by subtracting fiber and sugar alcohols from total carbohydr
Lean Body Mass Calculator Calculate lean body mass (LBM) from body fat percentage or using Boer, James, an
Fasting Calculator Calculate your intermittent fasting schedule for 16:8, 18:6, 20:4, OMAD, 5:2, an
Running Calorie Calculator Calculate calories burned running based on weight, distance, and pace. Includes
Blood Pressure Calculator Enter your systolic and diastolic readings to get your blood pressure category p
Walking Calorie Calculator Calculate calories burned walking based on weight, distance, and pace. Includes
Body Type Calculator Determine your body type (ectomorph, mesomorph, or endomorph) and frame size usi
Alcohol Calorie Calculator Calculate calories in alcoholic drinks including beer, wine, spirits, and cockta
Swimming Pace Calculator Calculate your swimming pace per 100 yards or meters, predict race times, plan s
Calorie Deficit Calculator Calculate the exact calorie deficit needed to reach your weight loss goal. Enter
Egg Freezing Calculator Calculate egg freezing costs, estimated eggs retrieved by age, viable eggs, and
IVF Cost Calculator Calculate total IVF cost including procedure, medications, PGT-A genetic testing
VO2 Max Calculator Calculate your VO2 max (maximal oxygen uptake) from a Cooper 12-minute run, 1.5
Body Recomposition Calculator Calculate your lean mass, fat mass, and target weight for body recomposition. Fi
Alcohol Unit Calculator Calculate UK alcohol units, US standard drinks, and calories in any drink. Track
GFR Calculator Calculate GFR and creatinine clearance using the Cockcroft-Gault equation. Get C
eGFR Calculator Calculate estimated GFR using the race-free CKD-EPI 2021 equation. Includes MDRD
Creatinine Clearance Calculator Calculate creatinine clearance (CrCl) using Cockcroft-Gault for drug dosing. Inc
A1C to Glucose Calculator Convert HbA1c to estimated average glucose (eAG) in mg/dL or mmol/L. Includes re
QT Interval Calculator Calculate corrected QT interval (QTc) using Bazett, Fridericia, and Hodges formu
APGAR Score Calculator Calculate newborn APGAR scores at 1, 5, and 10 minutes. Score appearance, pulse,
Pediatric Dose Calculator Calculate pediatric drug doses by weight (mg/kg) or body surface area (mg/m²). I
LDL Cholesterol Calculator Calculate LDL cholesterol using the Friedewald equation (TC – HDL – TG/5) or the
Mean Arterial Pressure Calculator Calculate mean arterial pressure (MAP) from systolic and diastolic blood pressur
Implantation Calculator Calculate your estimated implantation date from ovulation, LMP, or IVF transfer
hCG Doubling Time Calculator Calculate hCG doubling time from two beta hCG levels and days between tests. Ass
Waist-to-Height Ratio Calculator Calculate your waist-to-height ratio (WHtR) and assess cardiometabolic risk. A W
Pregnancy Weeks to Months Calculator Convert pregnancy weeks to months and find your trimester. Uses ACOG term defini
Postpartum Recovery Calculator Calculate your postpartum recovery timeline from your birth date. Get 2-week and
Wilks Calculator Calculate your Wilks score to compare powerlifting performance across different
DOTS Calculator Calculate your DOTS score — the 2020 powerlifting strength-scoring formula desig
IPF Points Calculator Calculate IPF GL Points — the International Powerlifting Federation official sco
VDOT Running Calculator Calculate your VDOT from any race time (mile through marathon). Get training pac
Marathon Pace Calculator Calculate your required marathon pace for any goal time. Get per-km and per-mile
Cycling FTP Calculator Calculate your Functional Threshold Power (FTP) from 20-minute test, 8-minute te
Cycling Power Zones Calculator Calculate all 7 Coggan cycling power training zones from your FTP. Includes Brit
Training Load Calculator Calculate TSS (Training Stress Score), CTL (fitness), ATL (fatigue), and TSB (fo
CHA₂DS₂-VASc Score Calculator Calculate CHA₂DS₂-VASc score for stroke risk in atrial fibrillation. Get annual
HAS-BLED Score Calculator Calculate HAS-BLED bleeding risk score for AFib patients on anticoagulation. Ide
GRACE Score Calculator Calculate the GRACE score for acute coronary syndrome mortality risk. Estimate i
TIMI Risk Score Calculator (UA/NSTEMI) Calculate the TIMI risk score for unstable angina and NSTEMI. Estimate 14-day MA
TIMI Risk Score for STEMI Calculate the TIMI risk score for STEMI. Estimate 30-day mortality risk using 8
ASCVD 10-Year Risk Calculator Calculate 10-year atherosclerotic cardiovascular disease (ASCVD) risk using the
Framingham Risk Score Calculator Calculate the Framingham 10-year coronary heart disease (CHD) risk score. Based
Ankle-Brachial Index (ABI) Calculator Calculate ankle-brachial index (ABI) to screen for peripheral artery disease (PA
Killip Class Calculator Determine Killip class for heart failure severity after acute myocardial infarct
NYHA Functional Classification Calculator Determine NYHA heart failure functional class (I-IV). Includes ACC/AHA Stage com
ROSE Rule Syncope Calculator Calculate the ROSE rule for syncope risk stratification in the emergency departm
Duke Treadmill Score (DTS) Calculator Calculate the Duke Treadmill Score from exercise stress test data. Formula: Exer
EuroSCORE II Calculator Calculate EuroSCORE II predicted in-hospital mortality for cardiac surgery. 18 r
CRUSADE Bleeding Score Calculator Calculate CRUSADE bleeding risk score for NSTEMI patients undergoing PCI. 8 vari
Mehran Score Calculator (Contrast-Induced Nephropathy) Calculate Mehran score for contrast-induced nephropathy (CIN) risk after PCI. 8
Modified Rankin Scale (mRS) Calculator Calculate the Modified Rankin Scale (mRS) for stroke outcome and neurological di
RCRI (Revised Cardiac Risk Index) Calculator Calculate RCRI (Lee Index) for perioperative cardiac risk before non-cardiac sur
ABCD² Score Calculator for TIA Stroke Risk Calculate ABCD² score for 2-day and 7-day stroke risk after transient ischemic a
NIH Stroke Scale (NIHSS) Calculator Calculate NIHSS (NIH Stroke Scale) score for ischemic stroke severity. 15 items,
Glasgow Coma Scale (GCS) Calculator Calculate Glasgow Coma Scale (GCS) score for traumatic brain injury severity ass
Peak Flow Calculator Calculate predicted Peak Expiratory Flow Rate (PEFR) using Nunn & Gregg formula
FEV1/FVC Ratio Calculator Calculate FEV1/FVC ratio for obstructive lung disease diagnosis. Fixed ratio <0.
BODE Index Calculator Calculate BODE Index for COPD prognosis: BMI, FEV1% predicted, mMRC dyspnea scal
CURB-65 Calculator Calculate CURB-65 score for community-acquired pneumonia (CAP) severity. Five cr
Asthma Control Test (ACT) Calculator Calculate ACT score for asthma symptom control. 5-item validated questionnaire s
A-a Gradient Calculator Calculate alveolar-arterial (A-a) oxygen gradient from ABG values. PAO2 = FiO2 ×
PSI/PORT Score Calculator Calculate Pneumonia Severity Index (PSI/PORT) for community-acquired pneumonia r
Wells PE Score Calculator Calculate Wells Score for pulmonary embolism (PE) pretest probability. 7 criteri
qSOFA (Quick SOFA) Calculator Calculate qSOFA score for rapid sepsis screening. Three criteria: RR ≥22, altere
SOFA Score Calculator Calculate full SOFA score for ICU organ dysfunction assessment. Six systems: Res
MDRD GFR Calculator Calculate MDRD-4 and MDRD-6 estimated GFR for CKD staging. Uses the 1999/2006 MD
FENa Calculator (Fractional Excretion of Sodium) Calculate fractional excretion of sodium (FENa%) to differentiate prerenal AKI f
FEUrea Calculator (Fractional Excretion of Urea) Calculate fractional excretion of urea (FEUrea%) to differentiate prerenal AKI f
Anion Gap Calculator Calculate serum anion gap (Na − Cl − HCO3) for metabolic acidosis workup. Includ
Albumin-Corrected Anion Gap Calculator Calculate albumin-corrected anion gap to unmask hidden HAGMA in hypoalbuminemic
Urine Osmolality Calculator Calculate urine osmolality from spot urine electrolytes: UOsm = 2×(UNa+UK) + Glu
HOMA-IR Calculator Calculate HOMA-IR (Homeostatic Model Assessment of Insulin Resistance) from fast
FINDRISC Calculator (Finnish Diabetes Risk Score) Calculate FINDRISC score (0–26) for 10-year Type 2 diabetes risk. Eight factors:
FRAX Fracture Risk Calculator Estimate 10-year probability of major osteoporotic fracture and hip fracture usi
Corrected Calcium Calculator Calculate albumin-corrected serum calcium: Corrected Ca = Total Ca + 0.8 × (4.0
Glucose Infusion Rate (GIR) Calculator Calculate glucose infusion rate for neonatal IV dextrose therapy. GIR = (Dextros
Westley Croup Score Calculator Calculate Westley Croup Score to assess croup severity in children. Five criteri
PEWS Pediatric Early Warning Score Calculator Calculate PEWS (Pediatric Early Warning Score) — 3 domains scored 0-3 each, tota
Pediatric Maintenance Fluids Calculator (4-2-1 Rule) Calculate pediatric IV maintenance fluid rate using the Holliday-Segar 4-2-1 rul
Pediatric BMI Percentile Calculator Calculate BMI percentile for children ages 2-20 using CDC growth charts. Underwe
New Ballard Score Calculator Calculate gestational age using the New Ballard Score (12 criteria: 6 neuromuscu
Bishop Score Calculator — Cervical Readiness for Labor Induction Calculate the Bishop Score to assess cervical ripeness before labor induction. S
Modified Bishop Score Calculator — Cervical Ripeness Assessment Calculate the Modified Bishop Score (Calder Score) to assess cervical readiness
Hadlock Fetal Weight Calculator — Estimated Fetal Weight (EFW) Calculate estimated fetal weight (EFW) using the Hadlock III formula from BPD, H
Amniotic Fluid Index (AFI) Calculator — Oligohydramnios & Polyhydramnios Calculate the Amniotic Fluid Index (AFI) by summing four-quadrant ultrasound poc
PHQ-9 Depression Screening Calculator Score the 9-item Patient Health Questionnaire (PHQ-9) to screen for depression s
GAD-7 Anxiety Screening Calculator Score the 7-item Generalized Anxiety Disorder scale (GAD-7) to screen for anxiet
AUDIT Alcohol Use Disorder Identification Test Score the WHO AUDIT 10-item questionnaire to screen for hazardous and harmful al
Fagerström Test for Nicotine Dependence (FTND) Score the Fagerström Test for Nicotine Dependence (FTND) to assess tobacco depen
Montreal Cognitive Assessment (MoCA) Score Calculator Calculate Montreal Cognitive Assessment (MoCA) scores across 8 cognitive domains
Mini-Mental State Examination (MMSE) Score Calculator Calculate the Mini-Mental State Examination (MMSE) score across 5 cognitive doma
Hamilton Depression Rating Scale Calculator (HAM-D 17) Clinician-rated Hamilton Depression Rating Scale (HAM-D 17) calculator. Score al
Morphine Equivalent Daily Dose (MEDD) Calculator Calculate total Morphine Equivalent Daily Dose (MEDD/MME) for multiple concurren
Opioid Rotation and Conversion Calculator Calculate equianalgesic opioid doses when rotating between opioids. Applies inco
IV Drip Rate Calculator (gtts/min) Calculate IV gravity infusion drip rate in drops per minute (gtts/min) for any v
APACHE II Score Calculator — ICU Severity & Mortality Calculate APACHE II score from 12 acute physiology variables plus age and chroni
MEWS Calculator — Modified Early Warning Score for Ward Deterioration Calculate MEWS (Modified Early Warning Score) from 5 vital signs to detect early
NEWS2 Calculator — National Early Warning Score 2 (UK NHS Standard) Calculate NEWS2 score from 7 physiological parameters. The UK NHS standard for d
Wells DVT Score Calculator — Deep Vein Thrombosis Pre-test Probability Calculate Wells DVT score to estimate pre-test probability of deep vein thrombos
Centor Score Calculator — Strep Pharyngitis Probability Calculate the Modified Centor (McIsaac) score to estimate group A streptococcal
MASCC Score Calculator — Febrile Neutropenia Risk & Outpatient Suitability Calculate MASCC score to identify low-risk febrile neutropenia patients suitable
Revised Trauma Score Calculator — Trauma Triage and Survival Prediction Calculate the Revised Trauma Score (RTS) from GCS, systolic BP, and respiratory
Injury Severity Score (ISS) Calculator — Anatomical Trauma Severity Calculate Injury Severity Score (ISS) from AIS scores across 6 body regions. Est
Parkland Burn Formula Calculator — IV Fluid Resuscitation for Burns Calculate Parkland formula IV fluid requirements for burn resuscitation. Determi
NEXUS C-Spine Calculator — Cervical Spine Injury Clearance in Trauma Apply NEXUS low-risk criteria to determine whether cervical spine imaging is req
Absolute Neutrophil Count (ANC) Calculator — Neutropenia Severity & Chemo Safety Calculate ANC from WBC and differential. Grades neutropenia severity (NCI CTCAE)
MCH / MCHC Calculator — Red Blood Cell Indices & Anemia Workup Calculate MCV, MCH, and MCHC from hemoglobin, hematocrit, and RBC count. Classif
Reticulocyte Production Index Calculator — Corrected Retic & Anemia Workup Calculate the corrected reticulocyte percentage and Reticulocyte Production Inde
Blood Transfusion Volume Calculator — pRBC, Platelets & FFP Dosing Calculate pediatric pRBC transfusion volume (4 mL/kg per 1 g/dL), adult unit req
Iron Deficit Calculator (Ganzoni Formula) — Total Iron Dose & IV Iron Products Calculate total iron deficit using the Ganzoni formula. Determines IV iron dose
Karnofsky Performance Status Calculator — Oncology Functional Assessment Calculate Karnofsky Performance Status (KPS) score. Determines chemotherapy elig
ECOG Performance Status Calculator — Oncology Eligibility & KPS Conversion Determine ECOG performance status (0–5). Guides chemotherapy eligibility, clinic
Chemotherapy BSA Dose Calculator — Oncology Drug Dosing by Body Surface Area Calculate chemotherapy doses based on BSA (Mosteller formula). Covers paclitaxel
Carboplatin AUC Dose Calculator — Calvert Formula with GFR Capping Calculate carboplatin dose using the Calvert formula (AUC × [GFR + 25]). Applies
Absolute Lymphocyte Count (ALC) Calculator — Lymphopenia Grading & Differential Calculate ALC from WBC and lymphocyte percentage. Grades lymphopenia severity (N
Preeclampsia Risk Calculator — FMF/ACOG First-Trimester Screening Assess preeclampsia risk using maternal risk factors, biomarkers, and uterine ar
Gravidity & Parity (GTPAL) Calculator — Obstetric History Notation Calculate GTPAL obstetric notation from pregnancy history. Encodes Gravida, Term
Menstrual Cycle Length Calculator — Average Length & Regularity from History Calculate average menstrual cycle length and variability from 6 recent cycles. I
MELD Score Calculator — Liver Disease Severity & Transplant Priority Calculate MELD score from bilirubin, creatinine, and INR. Estimates 3-month mort
MELD-Na Calculator — Sodium-Adjusted MELD for Liver Disease Calculate MELD-Na score (sodium-adjusted MELD) from bilirubin, creatinine, INR,
Child-Pugh Score Calculator — Cirrhosis Severity Classification Calculate Child-Pugh score and class (A/B/C) from 5 parameters: bilirubin, album
Ranson Criteria Calculator — Acute Pancreatitis Severity & Mortality Calculate Ranson score from 5 admission and 6 48-hour criteria for acute pancrea
Glasgow (Imrie) Pancreatitis Score Calculator — Severity at 48 Hours Calculate Glasgow-Imrie pancreatitis score from 8 criteria assessed at 48 hours.
Maddrey Discriminant Function Calculator — Alcoholic Hepatitis Severity Calculate Maddrey discriminant function for alcoholic hepatitis severity. DF ≥32
Braden Scale Calculator — Pressure Injury Risk Assessment Calculate Braden Scale score (6–23) to assess pressure ulcer/injury risk. Six su
IV Pump Rate Calculator — Infusion Rate mL/hr Calculate IV pump infusion rate in mL/hr from ordered dose (mcg/kg/min, mg/hr, u
Insulin Drip Calculator — DKA, HHS & ICU Glycemic Protocol Calculate starting IV insulin infusion rate for DKA, HHS, and ICU hyperglycemia.
Vancomycin Dose Calculator — Loading, Maintenance & AUC-Guided Calculate vancomycin loading dose (25-30 mg/kg) and maintenance dose with interv
Aminoglycoside Dose Calculator — Gentamicin, Tobramycin, Amikacin Calculate gentamicin, tobramycin, and amikacin doses using once-daily (Hartford)
Acetaminophen Toxicity Calculator — Rumack-Matthew Nomogram & NAC Apply the Rumack-Matthew nomogram to determine NAC (N-acetylcysteine) indication
Norton Scale Calculator — Pressure Ulcer Risk Assessment Calculate Norton Scale score (5–20) for pressure ulcer risk from physical condit
PUSH Tool 3.0 — Pressure Ulcer Scale for Healing Calculator Calculate PUSH (Pressure Ulcer Scale for Healing) Tool 3.0 score (0–17) from wou
NRS-2002 Nutrition Risk Screening Calculator — Hospital Malnutrition Calculate NRS-2002 (Nutrition Risk Screening 2002) score for hospitalised patien
Canine Blood Volume Calculator — Dog TBV, Transfusion & Donation Estimate total blood volume (TBV) in dogs using 80 mL/kg (standard) or 90 mL/kg
Veterinary Anesthesia Dose Calculator — Dog, Cat, Rabbit, Horse Calculate veterinary anesthesia doses for dogs, cats, rabbits, and horses. Cover
Math Calculators
124 Percentage Calculator Calculate percentages instantly. Find X% of a number, what percent X is of Y, an
Fraction Calculator Add, subtract, multiply, and divide fractions. Get results as simplified fractio
Scientific Calculator Online scientific calculator supporting trigonometry, logarithms, square roots,
GPA Calculator Calculate your GPA from letter grades and credit hours. Supports A through F gra
Grade Calculator Find out what score you need on your final exam to achieve your desired course g
Average Calculator Calculate the mean, median, and mode of any set of numbers. Enter comma-separate
Standard Deviation Calculator Calculate population or sample standard deviation and variance for any data set.
Random Number Generator Generate random numbers between any min and max. Choose how many numbers and dec
Square Root Calculator Calculate the square root, cube root, and fourth root of any number. Instantly c
Exponent Calculator Calculate any base raised to any exponent. See results in standard and scientifi
Logarithm Calculator Calculate log base 10, natural log (ln), log base 2, or any custom base logarith
Quadratic Formula Calculator Solve quadratic equations ax²+bx+c=0 using the quadratic formula. Find roots, di
Triangle Calculator Calculate triangle area, perimeter, and all three angles from the three side len
Pythagorean Theorem Calculator Calculate hypotenuse or missing leg using the Pythagorean theorem a²+b²=c². Find
GCD & LCM Calculator Calculate the Greatest Common Divisor (GCD) and Least Common Multiple (LCM) of t
Long Division Calculator Perform long division and find the quotient, remainder, and decimal result for a
Mixed Number Calculator Add, subtract, multiply, and divide mixed numbers. Get results as mixed numbers,
Probability Calculator Calculate probability, odds in favor, odds against, and complementary probabilit
Variance Calculator Calculate population variance (σ²) or sample variance (s²) for any data set. Als
Matrix Calculator Calculate the determinant, inverse, and matrix multiplication for 2×2 and 3×3 ma
Slope Calculator Calculate the slope (rise over run), y-intercept, line equation, and distance be
Ratio Calculator Solve proportions (A:B = C:?), simplify ratios to lowest terms, scale recipes, a
Z-Score Calculator Calculate the z-score from a raw score, mean, and standard deviation. Instantly
Circle Calculator Calculate circle area, circumference, and diameter from the radius, diameter, or
Percentage Change Calculator Calculate the percentage change between two values, percent difference, cumulati
Interpolation Calculator Calculate interpolated values between known data points. Supports linear interpo
Combination and Permutation Calculator Calculate combinations (nCr) and permutations (nPr) with or without repetition.
Scientific Notation Calculator Convert numbers to and from scientific notation, engineering notation, and E-not
Modulo Calculator Calculate the modulo (remainder) of any division. Supports negative numbers in b
Weighted Average Calculator Calculate the weighted average of up to 8 values. See total weight, each value's
Midpoint Calculator Find the midpoint between two points in 2D or 3D. Also calculates distance, slop
Moving Average Calculator Calculate Simple Moving Average (SMA), Exponential Moving Average (EMA), and Wei
Chi-Square Calculator Calculate the chi-square statistic for goodness of fit or test of independence.
Margin of Error Calculator Calculate margin of error for surveys and polls. Enter sample size, confidence l
Median Calculator Find the median of a dataset instantly. Also calculates mean, mode, quartiles (Q
Absolute Value Calculator Calculate the absolute value of any number instantly. Find |a − b| distance, bat
Number Base Calculator Perform arithmetic (add, subtract, multiply, divide) in binary, octal, decimal,
Significant Figures Calculator Count significant figures in any number, round to N sig figs, convert to scienti
Cylinder Calculator Calculate cylinder volume, lateral surface area, and total surface area from rad
Sphere Calculator Calculate sphere volume, surface area, diameter, and circumference from radius.
Cone Calculator Calculate cone volume, lateral surface area, total surface area, and slant heigh
Trapezoid Calculator Calculate trapezoid area, perimeter, diagonals, and median. Supports isosceles t
Fibonacci Calculator Find the Nth Fibonacci number, generate sequences, check if a number is Fibonacc
Cross Product Calculator Calculate the cross product (A×B) of two 3D vectors, find the dot product, angle
Speed Distance Time Calculator Solve for speed, distance, or time given the other two values. Works in miles, k
Rectangle Calculator Calculate rectangle area, perimeter, and diagonal from length and width. Solve f
Prism Calculator Calculate prism volume and surface area for rectangular, triangular, and hexagon
Correlation Calculator Calculate Pearson correlation coefficient (r), r², Spearman rank correlation, p-
Regression Calculator Perform simple linear regression to find slope, y-intercept, and equation (y = m
Hexagon Calculator Calculate the area, perimeter, apothem, and diagonal of a regular hexagon from t
Ellipse Calculator Calculate the area, circumference, and eccentricity of an ellipse from semi-majo
Arc Length Calculator Calculate arc length, sector area, and chord length from radius and central angl
Confidence Interval Calculator Calculate confidence intervals for population means (z and t distributions) and
Surface Area Calculator Calculate surface area and lateral area for cubes, rectangular boxes, cylinders,
Derivative Calculator Calculate the derivative of any function at a point using numerical methods. Sup
Integral Calculator Calculate definite integrals of any function using Simpson's rule, trapezoid rul
Limit Calculator Calculate the limit of any function as x approaches a value or infinity. Checks
Partial Derivative Calculator Calculate partial derivatives ∂f/∂x and ∂f/∂y of multivariable functions numeric
Definite Integral Calculator Compute definite integrals using Simpson's rule, trapezoid rule, and adaptive qu
Improper Integral Calculator Evaluate improper integrals with infinite bounds or discontinuous integrands. Ch
Double Integral Calculator Compute double integrals over rectangular regions, polar coordinates, and genera
Triple Integral Calculator Compute triple integrals over rectangular boxes in Cartesian, cylindrical, and s
Taylor Series Calculator Compute Taylor series coefficients and polynomial approximations for any functio
Maclaurin Series Calculator Calculate Maclaurin series partial sums for eˣ, sin(x), cos(x), ln(1+x), 1/(1-x)
Fourier Series Calculator Calculate Fourier series coefficients (a₀, aₙ, bₙ) for square, sawtooth, and tri
Laplace Transform Calculator Look up Laplace transforms of standard functions: 1, t, tⁿ, e^(at), sin(at), cos
Inverse Laplace Transform Calculator Find inverse Laplace transforms using standard tables: L⁻¹{1/s}=u(t), L⁻¹{1/(s−a
Riemann Sum Calculator Calculate Riemann sums using left, right, or midpoint endpoints. Compare with tr
Implicit Differentiation Calculator Calculate dy/dx for implicit equations F(x,y)=0 using numerical partial derivati
Second Derivative Calculator Calculate the second derivative f''(x) numerically using a 5-point stencil. Test
Chain Rule Calculator Calculate the derivative of composite functions g(f(x)) using the chain rule: d/
Arc Length Integral Calculator Calculate the arc length of a curve y=f(x) using L=∫√(1+(f')²)dx (Simpson's rule
Volume of Revolution Calculator Calculate volumes of revolution using disk method (V=π∫f²dx), shell method (V=2π
Tangent Line Calculator Find the tangent line equation y=f(x₀)+f'(x₀)(x−x₀) at any point. Also computes
Expected Value Calculator Calculate expected value EV = Σ(p × v) for 3–5 discrete outcomes. Includes varia
Euler Totient Calculator φ(n) Compute Euler's totient function φ(n): count of integers from 1 to n that are co
Modular Inverse Calculator Find the modular inverse a⁻¹ mod m using the Extended Euclidean Algorithm. Shows
Chinese Remainder Theorem Calculator Solve systems of simultaneous congruences x ≡ a₁ (mod m₁), x ≡ a₂ (mod m₂), … us
Extended Euclidean Algorithm Calculator Compute gcd(a,b) and Bézout coefficients x, y such that a·x + b·y = gcd(a,b). So
RSA Key Calculator Generate RSA public and private keys from primes p and q. Compute n=p×q, φ(n)=(p
Continued Fraction Calculator Convert rational numbers or decimals to continued fraction form [a₀; a₁, a₂, …].
Pascal's Triangle Calculator Compute any row of Pascal's Triangle, find specific binomial coefficients C(n,k)
Catalan Number Calculator Compute Catalan numbers Cₙ = C(2n,n)/(n+1). Explore the sequence 1,1,2,5,14,42,1
Sin Cos Tan Calculator Calculate sin, cos, tan, csc, sec, and cot for any angle in degrees or radians.
Inverse Trig Calculator Find angles from trig values using arcsin, arccos, and arctan. Get principal val
Law of Sines Calculator Solve any triangle using the Law of Sines: a/sin(A) = b/sin(B) = c/sin(C). Cover
Law of Cosines Calculator Solve triangles using the Law of Cosines: c² = a² + b² − 2ab·cos(C). Handles SAS
Unit Circle Calculator Find (cos θ, sin θ) coordinates on the unit circle for any angle. Includes exact
Reference Angle Calculator Find the reference angle (acute angle with x-axis) for any angle in degrees, inc
Coterminal Angle Calculator Find coterminal angles (angles sharing the same terminal side) for any input. Re
Trig Identity Calculator Verify and compute trigonometric identities numerically. Covers all 3 Pythagorea
Arithmetic Sequence Calculator Calculate any term and partial sum of an arithmetic sequence. Find aₙ = a₁ + (n−
Geometric Sequence Calculator Calculate any term and partial sum of a geometric sequence using aₙ = a·rⁿ⁻¹ and
Determinant Calculator Calculate the determinant of 2x2, 3x3, or 4x4 matrices with cofactor expansion s
Matrix Inverse Calculator Find the inverse of 2x2 or 3x3 matrices using adjugate/determinant. Verify A*A-i
Eigenvalue Calculator Find eigenvalues and eigenvectors of 2x2 and 3x3 matrices. Solves det(A-lambda*I
RREF Calculator Compute the Reduced Row Echelon Form of any matrix via Gauss-Jordan elimination.
Vector Projection Calculator Calculate the vector projection proj_b(a) = (a·b/|b|²)·b and scalar projection c
Matrix Multiplication Calculator Multiply matrices A*B for 2x2, 3x3, and non-square (mxp * pxn) cases. Shows step
Gauss-Jordan Calculator Perform Gauss-Jordan elimination on augmented matrices [A|b]. Solve linear syste
Complex Number Calculator Perform complex number arithmetic (add, subtract, multiply, divide). Compute mod
Polar to Rectangular Converter Convert between polar (r, theta) and rectangular (x, y) coordinates. Supports de
Pythagorean Triple Calculator Generate all primitive Pythagorean triples (a,b,c) with a²+b²=c² up to a given h
Summation Calculator Calculate finite sums with sigma notation. Supports Σi, Σi², Σi³, telescoping se
Hash Collision Probability Calculator Calculate the probability of hash collisions using the birthday problem formula.
Big O Notation Calculator Calculate algorithm time and space complexity. Compare O(1), O(log n), O(n), O(n
XOR Calculator Calculate bitwise XOR (exclusive OR) of two numbers. Results in decimal, hex, an
Rounding Calculator Round any number to decimal places, significant figures, or the nearest 5/10/100
Percent Error Calculator Calculate percent error between an experimental measurement and the accepted the
Percent Difference Calculator Calculate percent difference between two values using the symmetric formula (ave
t-Test Calculator Calculate t-statistic, degrees of freedom, and p-value for one-sample, two-sampl
ANOVA Calculator Compute F-statistic, p-value, eta-squared effect size, and Tukey HSD for one-way
F-Test Calculator Compute the F-statistic for testing equality of two variances, ANOVA model fit,
p-Value Calculator Convert any test statistic (z, t, F, or χ²) into a p-value. Supports one-tailed
Bayes' Theorem Calculator Calculate posterior probability using Bayes' theorem. Supports standard form, me
Binomial Distribution Calculator Calculate exact, cumulative, and complementary binomial probabilities. Find P(X=
Poisson Distribution Calculator Calculate Poisson probabilities P(X=k), P(X≤k), and P(X≥k) for any rate λ. Inclu
Normal Distribution Calculator Calculate z-scores, P(X<x), P(X>x), and P(a<X<b) for any normal distribution. In
Range Calculator Calculate statistical range (max − min), compare range vs IQR and standard devia
Interquartile Range (IQR) Calculator Calculate IQR, Q1, Q2 (median), Q3, five-number summary, and detect outliers usi
Coefficient of Variation Calculator Calculate the coefficient of variation (CV = SD / Mean × 100%). Compare variabil
R-Squared Calculator Calculate R² (coefficient of determination) for linear regression. Measures how
Skewness Calculator Calculate the skewness of a dataset to measure distribution asymmetry. Includes
Kurtosis Calculator Calculate kurtosis and excess kurtosis of a dataset. Identifies leptokurtic (fat
Temperature Converter Convert temperature between Celsius, Fahrenheit, and Kelvin instantly. Free onli
Length Converter Convert length and distance between metric and imperial units. Supports mm, cm,
Weight Converter Convert weight and mass between kilograms, pounds, ounces, grams, stone, and met
Volume Converter Convert volume between milliliters, liters, US gallons, quarts, pints, cups, flu
Area Converter Convert area between square feet, square meters, acres, hectares, square yards,
Speed Converter Convert speed between miles per hour, kilometers per hour, meters per second, kn
Hex to Decimal Converter Convert hexadecimal numbers to decimal, binary, and octal instantly. Essential t
Binary to Decimal Converter Convert binary numbers to decimal, hexadecimal, and octal. Supports any binary i
Cups to Grams Converter Convert cups to grams for flour, sugar, butter, and other ingredients. Accurate
Feet and Inches to Meters Converter Convert feet and inches to meters and centimeters. Perfect for height conversion
Celsius to Fahrenheit Converter Convert Celsius to Fahrenheit and Kelvin instantly. Simple °C to °F conversion t
Inches to Centimeters Converter Convert inches to centimeters, millimeters, and meters instantly. Fast and accur
Ounces to Grams Converter Convert ounces to grams, kilograms, and pounds instantly. Accurate oz to g conve
Pounds to Kilograms Converter Convert pounds to kilograms, grams, and stone. Fast lbs to kg converter for body
Miles to Kilometers Converter Convert miles to kilometers, meters, and feet instantly. Accurate mi to km conve
Color Code Converter Convert color codes between HEX, RGB, and HSL formats. Essential tool for web de
Shoe Size Converter Convert shoe sizes between US, UK, and EU systems for men, women, and kids. Get
Pressure Converter Convert pressure between PSI, bar, atmospheres, kPa, mmHg, inHg, and Pascal. Inc
Military Time Converter Convert standard 12-hour time to military (24-hour) time and back. Get spoken mi
Data Transfer Rate Calculator Convert data transfer speeds between bps, Kbps, Mbps, Gbps, Tbps, Bps, KBps, MBp
Liters to Gallons Converter Convert liters to US gallons or UK (imperial) gallons instantly. Also convert fl
HP to kW Converter Convert horsepower to kilowatts (and back). Supports mechanical HP, metric HP (P
Torque Converter Calculator Convert torque between Newton-meters, foot-pounds, inch-pounds, and kilogram-for
Cooking Converter Convert cooking measurements: cups to ml, tbsp to tsp, oz to grams, and Fahrenhe
Energy Converter Convert energy between joules, kilocalories, BTU, kilowatt-hours, electron volts
Roman Numeral Converter Convert numbers to Roman numerals and Roman numerals back to numbers instantly.
Clothing Size Converter Convert clothing sizes between US, UK, EU, and Japan for men and women. Covers t
Base Converter Convert numbers between any bases from 2 to 36. Instantly see binary, octal, dec
Frequency Converter Convert between hertz, kilohertz, megahertz, gigahertz, terahertz, RPM, and BPM.
Fuel Economy Converter Convert fuel economy between US MPG, UK MPG, liters per 100km, and km per liter.
Decimal to Fraction Converter Convert any decimal to a simplified fraction or mixed number instantly. Also con
Lux to Lumens Calculator Convert between lux and lumens for any area. Includes a room lighting guide with
AWG to mm Converter Convert American Wire Gauge (AWG) to diameter in mm, cross-section area in mm²,
Base64 Converter Encode text to Base64 and decode Base64 back to text instantly. Supports standar
IP Address Converter Convert IPv4 addresses to binary (32-bit), hexadecimal, and decimal integer. Und
Age Calculator Calculate your exact age in years, months, and days from your birth date. Find o
Date Calculator Add or subtract days, months, and years from any date. Find what date it will be
Time Calculator Add or subtract hours and minutes from any time of day. Great for scheduling, sh
Hours Calculator Calculate the number of hours and minutes worked between a start time and end ti
Days Between Dates Calculator Find the exact number of days, weeks, and months between two dates. Useful for p
Time Zone Converter Convert a time from one time zone to another. Supports UTC offsets for all major
Countdown Calculator Find out exactly how many days, hours, and minutes remain until any future date.
Work Hours Calculator Calculate net daily work hours from start time, end time, and break. Extrapolate
Time Duration Calculator Convert a duration in hours, minutes, and seconds into total seconds, decimal ho
Unix Timestamp Converter Convert a Unix epoch timestamp to a human-readable date, or convert a date to a
Elapsed Time Calculator Calculate elapsed time between two times with AM/PM. Handles overnight crossing,
Week Number Calculator Find the ISO week number for any date. Includes US week numbering, fiscal week,
Age in Days Calculator Calculate your total days alive, hours, minutes, heartbeats, and fun facts. Find
Workday Calculator Count business days between two dates, excluding weekends and holidays. Add busi
Leap Year Calculator Check if any year is a leap year, list all leap years in a range, calculate leap
Gestational Age Calculator Calculate how many weeks pregnant you are from LMP, ultrasound CRL, or IVF trans
Sunrise Sunset Calculator Calculate sunrise time, sunset time, daylight hours, and solar noon for any loca
Timezone Overlap Calculator Find overlapping working hours between time zones. Compare 2 or 3 time zones and
Pay Date Calculator Find your next payday for weekly, bi-weekly, semi-monthly, and monthly pay sched
Date of Birth Calculator Find your birth year or birth date from your current age. Enter age in years, ye
Julian Date Converter Convert Gregorian calendar dates to Julian Day Numbers (JDN) and Modified Julian
Stopwatch Lap Calculator Calculate average lap time from total race time and number of laps. Analyze indi
Concrete Calculator Calculate how much concrete you need in cubic yards and cubic meters, plus the n
Square Footage Calculator Calculate the area of a rectangular space in square feet, square meters, and acr
Paint Calculator Calculate how many gallons of paint you need for a room. Accounts for walls, cei
Tile Calculator Calculate the number of tiles needed for a floor or wall. Includes waste percent
Flooring Calculator Calculate how much flooring you need in square feet, including a waste percentag
Roofing Calculator Calculate how many roofing squares, shingle bundles, and sheets of underlayment
Mulch Calculator Calculate cubic yards and cubic feet of mulch needed for any garden bed or lands
Gravel Calculator Calculate how many tons and cubic yards of gravel, crushed stone, or pea gravel
Fence Calculator Calculate how many fence posts, rails, and boards you need for any fencing proje
Deck Calculator Estimate deck boards, joists, and support posts needed for a deck based on dimen
Drywall Calculator Calculate how many sheets of drywall (4×8 or 4×12) you need for walls and ceilin
Wallpaper Calculator Calculate how many rolls of wallpaper you need for a room, accounting for patter
Insulation Calculator Calculate how many batts or rolls of insulation you need for walls, attics, or c
Stair Calculator Calculate stair dimensions: number of risers, riser height, tread depth, total r
Paver Calculator Calculate how many pavers you need for any patio, walkway, or driveway. Enter ar
Siding Calculator Calculate how many squares of siding you need for any wall. Enter wall dimension
Retaining Wall Calculator Calculate how many retaining wall blocks you need, number of courses, cap blocks
Soil Calculator Calculate how much soil, topsoil, or garden mix you need in cubic feet, cubic ya
Rebar Calculator Calculate how many rebar bars you need for any concrete slab, footing, or column
Concrete Steps Calculator Calculate concrete volume in cubic feet, cubic yards, and 80 lb bags for steps a
Concrete Block Calculator Calculate how many concrete blocks (CMU) you need for any wall. Get block count
Land Area Calculator Calculate land area in square feet, square yards, acres, and hectares for rectan
Asphalt Calculator Calculate how much asphalt you need in tons and cubic yards for driveways, parki
Pool Volume Calculator Calculate swimming pool volume in gallons, liters, and cubic feet for rectangula
Concrete Slab Calculator Calculate concrete cubic yards, bags, rebar grid, sub-base, form boards, and tot
Concrete Footing Calculator Calculate concrete volume for continuous footings, pier (sonotube) footings, and
Carpet Calculator Calculate how much carpet you need in square feet and square yards, including wa
BTU Calculator Calculate the BTU needed to cool or heat a room based on square footage, ceiling
Concrete Yard Calculator Calculate exact cubic yards of concrete to order for delivery. Includes waste fa
Concrete Driveway Cost Calculator Estimate the total cost to pour a concrete driveway including materials, labor,
Snow Load Calculator Calculate the total weight of snow on your roof in pounds and pounds per square
Sand Calculator Calculate how much sand you need in cubic feet, cubic yards, tons, and 50 lb bag
Lumber Calculator Calculate board feet of lumber and total cost for any woodworking or constructio
Generator Size Calculator Calculate the right generator size in kW for your home or job site. Enter total
Bathroom Remodel Calculator Estimate bathroom remodel costs by size and remodel level. Get detailed cost bre
Kitchen Remodel Calculator Estimate kitchen remodel costs by size and remodel level. Get a detailed cost br
Heat Pump Size Calculator Calculate the right heat pump size in BTUs and tons for your home based on squar
Plywood Calculator Calculate how many plywood sheets you need for any project. Enter area dimension
Fence Post Calculator Calculate the number of fence posts, post hole depth, concrete bags per hole, an
Epoxy Floor Calculator Calculate how much epoxy primer, base coat, and top coat you need for any floor
Gutter Calculator Calculate how many linear feet of gutter, number of downspouts, end caps, and co
Window Replacement Cost Calculator Estimate window replacement cost per window and total project cost. Compare viny
Solar Panel Calculator Calculate how many solar panels you need, system size in kW, annual savings, pay
Backsplash Calculator Calculate how many tiles you need for your kitchen or bathroom backsplash. Enter
Water Heater Size Calculator Calculate the right water heater size for your home. Find recommended tank size
Brick Calculator Calculate how many clay or face bricks you need for a wall, including mortar bag
Cubic Yard Calculator Calculate volume in cubic yards, cubic feet, and gallons for any material. Recta
Duct Size Calculator Calculate round duct diameter and rectangular equivalent for any CFM airflow req
Steel Weight Calculator Calculate the weight of steel plates, round bars, square bars, pipes, and angles
Gas Pipe Sizing Calculator Size natural gas or propane pipes by BTU load and pipe length. Supports 2 PSI, 0
Framing Calculator Calculate wall studs, top and bottom plates, and total lumber for framing projec
Pipe Flow Calculator Calculate pipe flow rate in GPM and CFM, flow velocity, Reynolds number, and pre
Concrete Ramp Calculator Calculate concrete volume for a ramp in cubic feet, cubic yards, and 80-lb bags.
Stucco Calculator Calculate stucco mix bags, wire lath, and mesh rolls for any wall. Supports 2 or
Sod Calculator Calculate how many sod rolls and pallets you need, plus installation cost, topso
Cable Length Calculator Calculate total cable needed for a network or wiring project. Find total wire ru
Concrete Mix Calculator Calculate cement bags, sand, and gravel needed for any concrete mix ratio. Suppo
Roof Pitch Calculator Calculate roof pitch ratio (4:12, 6:12, etc.), angle in degrees, rafter length,
Area of Irregular Shape Calculator Calculate the area and perimeter of any irregular polygon using the Shoelace for
Tank Volume Calculator Calculate industrial and agricultural tank volume in gallons, liters, and oil ba
Shingle Calculator Calculate how many asphalt shingle bundles you need for your roof. Enter roof ar
Foundation Calculator Calculate concrete cubic yards, rebar linear feet, and formwork area for slab, s
Pea Gravel Calculator Calculate how much pea gravel you need in cubic yards, tons, and 50 lb bags for
River Rock Calculator Calculate how much river rock you need in cubic yards and tons for landscaping b
Landscape Edging Calculator Calculate how many landscape edging pieces you need by entering bed perimeter in
Countertop Calculator Calculate countertop square footage for standard counters, islands, L-shape, and
Baseboard Calculator Calculate how much baseboard trim you need in linear feet and 8- or 16-foot piec
Crown Molding Calculator Calculate how much crown molding you need in linear feet and 8- or 12-foot piece
Driveway Sealcoat Calculator Calculate how many gallons of driveway sealer you need for 1-coat or 2-coat appl
Chimney Flue Size Calculator Calculate the required chimney flue diameter and minimum height for wood stoves,
Water Feature Pump Calculator Size a pond or fountain pump in GPH. Enter water volume, turnover rate, and head
Duct Velocity Calculator Calculate air velocity in feet per minute (FPM) through round or rectangular duc
Pool Heater Size Calculator Calculate the BTU/hr heater size needed to heat your pool. Covers gas, electric,
Cabinet Calculator Calculate kitchen cabinet linear feet for L-shaped, U-shaped, and galley layouts
Wind Load Calculator Calculate structural wind pressure in PSF using ASCE 7 velocity pressure and exp
Ohm's Law Calculator Calculate voltage, current, or resistance using Ohm's Law. Enter any two values
Voltage Calculator Calculate electrical voltage from current and resistance, or from power and curr
Resistor Color Code Calculator Decode resistor color bands to find resistance value and tolerance. Supports 4-b
Speed Calculator Calculate speed from distance and time, distance from speed and time, or time fr
Density Calculator Calculate density from mass and volume, mass from density and volume, or volume
Force Calculator Calculate force, mass, or acceleration using Newton's Second Law F = ma. Support
Molar Mass Calculator Find the molar mass of common elements and chemical compounds in g/mol. Instantl
pH Calculator Calculate pH from hydrogen ion concentration [H⁺], or find [H⁺] and [OH⁻] from a
Half-Life Calculator Calculate the remaining amount of a radioactive substance after a given time usi
Sample Size Calculator Calculate the required sample size for surveys, experiments, and A/B tests. Supp
Dilution Calculator Calculate solution dilutions using C1V1 = C2V2. Find final volume, concentration
Wire Size Calculator Find the correct AWG wire size for any electrical circuit based on amperage, dis
Dew Point Calculator Calculate dew point from air temperature and relative humidity using the Magnus
Amps to Watts Calculator Convert amps to watts for DC, single-phase AC, and three-phase AC circuits. Get
Wind Chill Calculator Calculate wind chill temperature using the NWS formula. Enter air temperature an
Heat Index Calculator Calculate the heat index (feels-like temperature) from air temperature and relat
Molarity Calculator Calculate molarity (mol/L) from solute mass, molar mass, and solution volume. Fi
Electric Field Calculator Calculate electric field strength (N/C) from a point charge, parallel plates, or
Acceleration Calculator Calculate acceleration from velocity change, force, or free fall. Includes g-for
Wavelength Calculator Convert frequency to wavelength (and back) in vacuum, air, or water. Identify th
Electricity Carbon Calculator Calculate CO₂ emissions from electricity usage. Enter monthly kWh and select you
Noise Level Calculator Calculate combined decibel levels from multiple sound sources, find dB at distan
Air Quality Index Calculator Calculate AQI from PM2.5, PM10, or Ozone concentrations. Get your air quality ca
Voltage Drop Calculator Calculate voltage drop over wire distance for single-phase and three-phase circu
Kinetic Energy Calculator Calculate kinetic energy from mass and velocity. Supports relativistic KE, rotat
Momentum Calculator Calculate linear momentum (p = mv), impulse, and collision outcomes. Covers elas
Ideal Gas Law Calculator Solve PV = nRT for any variable. Supports combined gas law, gas density, Van der
Pendulum Calculator Calculate pendulum period, frequency, and angular frequency from length and grav
Specific Heat Calculator Calculate heat energy, temperature change, or mass using Q = mcΔT. Includes mate
Spring Constant Calculator Calculate spring constant (k), force, or displacement using Hooke's Law. Covers
Projectile Motion Calculator Calculate projectile range, maximum height, and time of flight. Enter initial ve
Capacitance Calculator Calculate capacitance from charge and voltage (C=Q/V), energy stored (½CV²), par
Buoyancy Calculator Calculate buoyant force, apparent weight, and whether an object floats or sinks
Friction Calculator Calculate friction force from normal force and coefficient of friction. Covers f
Bandwidth Calculator Calculate required internet bandwidth for file transfers, video streaming (720p/
Thermal Expansion Calculator Calculate linear, area, and volumetric thermal expansion for 8+ materials. Inclu
Work Energy Calculator Calculate work done by a force using W = Fd cos(θ). Includes Work-Energy Theorem
Heat Transfer Calculator Calculate heat transfer rate (W) and heat flux (W/m²) for conduction, convection
Power Calculator Calculate mechanical power from work & time (P=W/t), force & velocity (P=Fv), or
Centripetal Force Calculator Calculate centripetal force and acceleration from mass, velocity, and radius. So
Elastic Potential Energy Calculator Calculate elastic potential energy stored in a spring using ½kx². Find energy fr
Wave Speed Calculator Calculate wave speed using v = fλ. Solve for speed, frequency, or wavelength. In
Beat Frequency Calculator Calculate beat frequency from two sound waves. Find beat rate |f₁−f₂|, beat peri
Sound Intensity Calculator Convert sound intensity (W/m²) to decibels (dB) and back. Calculate sound pressu
Telescope Magnification Calculator Calculate telescope magnification (M = f_obj / f_eye), maximum useful magnificat
Snell's Window Calculator Calculate Snell's window critical angle (θ_c = arcsin(1/n) ≈ 48.6° for water), w
Snell's Law Calculator Calculate the angle of refraction using Snell's Law (n₁sinθ₁ = n₂sinθ₂). Find re
Thin Lens Calculator Calculate image distance and magnification using the thin lens equation 1/f = 1/
Mirror Equation Calculator Calculate image distance and magnification for concave, convex, and plane mirror
Lensmaker's Equation Calculator Calculate lens focal length from surface radii and refractive index using the le
Magnification Calculator Calculate optical magnification from object and image heights (m = hᵢ/hₒ) or dis
Focal Length Calculator Calculate focal length from object and image distances (1/f = 1/dₒ + 1/dᵢ), from
Diopter Calculator Convert between focal length and diopters (optical power). Calculate combined po
Refractive Index Calculator Calculate refractive index n = c/v from light speed in medium, look up n for 50+
Critical Angle Calculator Calculate the critical angle for total internal reflection: θ_c = arcsin(n₂/n₁).
Doppler Effect Calculator Calculate the Doppler frequency shift for moving sources and observers. Covers s
Henderson-Hasselbalch Calculator Calculate buffer pH using the Henderson-Hasselbalch equation. Enter pKa and conj
Stoichiometry Calculator Convert between mass, moles, and molecules across a balanced chemical equation.
Limiting Reactant Calculator Identify the limiting reactant in a chemical reaction. Enter moles or masses of
Percent Yield Calculator Calculate percent yield from actual and theoretical yields. Includes atom econom
Empirical Formula Calculator Calculate the empirical formula from percent composition or element masses. Dete
Titration Calculator Calculate the molarity of an unknown acid or base from titration data. Supports
Gibbs Free Energy Calculator Calculate ΔG from ΔH and ΔS, from equilibrium constant K, or from cell potential
Enthalpy Calculator Calculate the enthalpy of reaction (ΔH_rxn) using Hess's Law from standard entha
Rate of Reaction Calculator Calculate reaction rate using the rate law r = k[A]ⁿ, from concentration changes
Activation Energy Calculator Calculate activation energy Ea from two rate constants at two temperatures using
Escape Velocity Calculator Calculate escape velocity from any planet or body using mass and radius. Include
Orbital Period Calculator Calculate orbital period using Kepler's Third Law (T = 2π√(a³/GM)). Supports AU/
Orbital Velocity Calculator Calculate circular orbital velocity (v = √(GM/r)) or elliptical velocity using t
Gravitational Force Calculator Calculate the gravitational force between two masses using Newton's law F = Gm₁m
Surface Gravity Calculator Calculate surface gravity (g = GM/r²) for any planet or body. Shows g in m/s² an
Light-Year Converter Convert between light-years, parsecs, AU, kilometers, miles, and light-seconds.
Parsec Calculator Convert stellar parallax angle (arcseconds) to distance in parsecs and light-yea
Hubble Law Calculator Calculate galaxy recession velocity from Hubble's Law (v = H₀d). Shows Hubble te
Redshift Calculator Calculate cosmological redshift z from observed and emitted wavelengths, or from
Schwarzschild Radius Calculator Calculate the Schwarzschild radius (event horizon) of a black hole from its mass
Freezing Point Depression Calculator Calculate freezing point depression using ΔTf = i × Kf × m. Supports water, benz
Boiling Point Elevation Calculator Calculate boiling point elevation using ΔTb = i × Kb × m. Supports water, benzen
Hardy-Weinberg Equilibrium Calculator Calculate Hardy-Weinberg equilibrium genotype frequencies from allele frequencie
Michaelis-Menten Calculator Calculate enzyme reaction rates using the Michaelis-Menten equation. Find Km, Vm
Cell Doubling Time Calculator Calculate cell doubling time (td) and specific growth rate (μ) from cell counts.
Punnett Square Calculator Calculate Mendelian inheritance outcomes with a Punnett square. Supports monohyb
Altitude Oxygen Calculator Calculate atmospheric pressure in mbar/atm and partial pressure of oxygen (mmHg)
Bernoulli Equation Calculator Calculate fluid pressure at any point using the Bernoulli equation. Enter pressu
Reynolds Number Calculator Calculate Reynolds number from fluid density, velocity, characteristic length, a
Terminal Velocity Calculator Calculate terminal velocity for any object in air or fluid. Enter mass, drag coe
Coulomb's Law Calculator Calculate the electrostatic force between two point charges using Coulomb's law
Drag Force Calculator Calculate aerodynamic or fluid drag force using F_D = ½ρv²CdA. Covers high-Reyno
Inductor Reactance Calculator Calculate inductive reactance XL = 2πfL for any inductance and frequency. Covers
RLC Circuit Calculator Calculate impedance Z, resonant frequency, Q factor, bandwidth, phase angle, and
Transformer Turns Ratio Calculator Calculate secondary voltage, current, and impedance for power transformers. Ente
Half-Life Decay Chain Calculator Calculate parent and daughter isotope activities in multi-step radioactive decay
Nuclear Binding Energy Calculator Calculate nuclear binding energy and mass defect from proton/neutron counts and
Relativistic Velocity Calculator Calculate relativistic velocity addition, Lorentz factor γ, time dilation, and l
Photon Energy Calculator Calculate photon energy E = hf = hc/λ in Joules and electron volts from waveleng
Earthquake Magnitude Calculator Calculate Richter local magnitude (Mₗ) from amplitude and distance, convert to m
Earthquake Energy Calculator Calculate the energy released by any earthquake magnitude in joules, TNT equival
Mohr's Circle Calculator Calculate principal stresses σ₁ and σ₂, maximum shear stress τmax, and principal
Mineral Density Calculator Calculate mass from mineral density and volume. Covers rock-forming minerals, or
Tsunami Travel Time Calculator Calculate tsunami wave speed and travel time across ocean basins using the shall
Profit Margin Calculator Calculate gross profit margin percentage and gross profit from revenue and cost.
Markup Calculator Calculate selling price and profit from cost and markup percentage. Understand t
Break-Even Calculator Find how many units you need to sell to cover all costs. Calculate your break-ev
VAT Calculator Add or remove VAT from any price. Calculate VAT amount and total price inclusive
Discount Calculator Quickly calculate the sale price and how much you save with any discount percent
Commission Calculator Calculate commission earned from a sale. Add base salary to find total compensat
Freelance Rate Calculator Calculate the minimum hourly rate you need to charge as a freelancer to hit your
Invoice Calculator Calculate invoice totals with multiple line items, tax, and optional discounts.
Hourly Rate Calculator Convert annual salary to hourly, daily, and monthly rates. See what your $60k, $
Depreciation Calculator Calculate annual asset depreciation using straight-line or double-declining bala
Time Card Calculator Calculate hours worked and gross pay from clock-in/out times. Supports daily, we
Overtime Calculator Calculate regular pay, overtime pay, and total gross wages. Includes biweekly to
Salary to Hourly Calculator Convert your annual salary to an hourly rate. Get daily, weekly, and monthly rat
Net Income Calculator Calculate business net income from revenue and expenses. Includes gross profit,
Business Loan Calculator Calculate business loan payments for term loans, SBA loans, and lines of credit.
Inventory Turnover Calculator Calculate inventory turnover ratio, days sales of inventory (DSI), GMROI, carryi
Working Capital Calculator Calculate working capital, current ratio, quick ratio, cash ratio, and cash conv
Cash Flow Calculator Calculate business cash flow, free cash flow, burn rate, and runway. Includes qu
Payback Period Calculator Calculate simple and discounted payback period for investments. Includes NPV, IR
Meeting Cost Calculator Calculate the true cost of business meetings by attendee count, hourly rate, and
Churn Rate Calculator Calculate customer churn rate, retention rate, MRR impact, and net revenue churn
Customer Lifetime Value Calculator Calculate customer lifetime value (CLV/LTV) using purchase frequency, average or
Net Promoter Score Calculator Calculate your Net Promoter Score (NPS) from promoters, passives, and detractors
Cost Per Unit Calculator Calculate manufacturing cost per unit from fixed and variable costs. Find break-
Employee Turnover Calculator Calculate employee turnover rate, retention rate, and the annual cost of turnove
Data Storage Cost Calculator Calculate cloud storage costs for AWS S3, Google Cloud, and Azure Blob Storage.
CPM Calculator Calculate CPM (Cost Per 1,000 Impressions), CPC, CTR, CPA, and ROAS for your adv
Revenue per Employee Calculator Calculate revenue per employee, FTE-adjusted revenue, profit per employee, and l
Lead Time Calculator Calculate lead time between order date and delivery date in calendar days, busin
Gross Margin Calculator Calculate gross profit, gross margin percentage, and markup from revenue and COG
CPC Calculator Calculate cost per click (CPC) from ad spend and clicks. Find required budget fr
Conversion Rate Calculator Calculate website conversion rate from visitors and conversions. Analyze e-comme
Revenue Growth Calculator Calculate revenue growth rate between two periods. Analyze MoM, QoQ, YoY growth,
MRR Calculator Calculate Monthly Recurring Revenue (MRR) from customers and ARPU. Track net new
ARR Calculator Calculate Annual Recurring Revenue (ARR) from MRR, ACV, or multi-year contracts.
Customer Acquisition Cost (CAC) Calculator Calculate Customer Acquisition Cost (CAC) from sales & marketing spend. Compare
LTV:CAC Ratio Calculator Calculate your LTV:CAC ratio to evaluate SaaS unit economics. Find gross-margin-
CAC Payback Period Calculator Calculate CAC payback period (CAC ÷ Monthly Gross Profit). Compare SMB, mid-mark
Startup Burn Rate Calculator Calculate gross burn rate, net burn rate, and runway months for your startup. In
Startup Runway Calculator Calculate how many months of runway your startup has. See projected zero-cash da
Net Revenue Retention Calculator Calculate NRR from starting MRR, expansion, contraction, and churn. Benchmark ag
Gross Revenue Retention Calculator Calculate GRR from starting MRR, contraction, and churn (capped at 100%). Compar
Rule of 40 Calculator Calculate your Rule of 40 score (revenue growth % + EBITDA or FCF margin %). Ben
SaaS Magic Number Calculator Calculate the SaaS Magic Number (4 × Net New ARR / S&M Spend). Benchmark sales e
SaaS Quick Ratio Calculator Calculate SaaS Quick Ratio (new + expansion MRR) / (churn + contraction MRR). Be
Equity Dilution Calculator Calculate founder equity dilution from investment rounds. Model pre/post-money v
Startup Valuation Calculator Estimate startup valuation using revenue multiples by sector and growth rate. In
SAFE Note Calculator Calculate SAFE note conversion price, ownership percentage, and dilution at Seri
Mileage Reimbursement Calculator Calculate IRS-standard mileage reimbursement for business ($0.70/mi), medical ($
Influencer Rate Calculator Calculate your influencer rate per post, story, reel, or YouTube video based on
YouTube Money Calculator Estimate YouTube ad revenue from monthly views and RPM. Compare earnings by nich
TikTok Money Calculator Estimate TikTok earnings from Creator Rewards Program ($0.40–1.00 per 1K views f
Twitch Revenue Calculator Calculate Twitch streamer income from subscriptions (Tier 1/2/3 and Prime), Bits
Shopify Profit Calculator Calculate Shopify store net profit after subscription fees ($39–$399/mo), paymen
Amazon FBA Calculator Calculate Amazon FBA fees including referral fee (8–17% by category), fulfillmen
Etsy Fee Calculator Calculate Etsy seller fees: $0.20 listing fee, 6.5% transaction fee on item + sh
Patreon Revenue Calculator Calculate Patreon net revenue after platform fee (Lite 5%, Pro 8%, Premium 12%)
Spotify Streaming Revenue Calculator Calculate Spotify streaming revenue at $0.003–0.005 per stream. Compare platform
SEO Traffic Value Calculator Calculate the monetary value of organic search traffic using CTR by position and
Keyword Difficulty Calculator Calculate keyword difficulty score (0-100) based on top-10 competitor backlinks
Engagement Rate Calculator Calculate social media engagement rate by followers, reach, or post average. Com
Gas Mileage Calculator Calculate your car's fuel economy in MPG and cost per mile. Track fuel efficienc
Fuel Cost Calculator Estimate the total fuel cost for any road trip. Enter distance, MPG, and gas pri
Electricity Cost Calculator Calculate how much any appliance or device costs to run. Find daily, monthly, an
Dog Age Calculator Convert your dog's age to human years by breed size. The modern formula accounts
Snow Day Calculator Estimate the probability of a snow day school closure based on forecasted snowfa
Dice Roller Roll virtual dice for tabletop RPGs, board games, and decisions. Supports D4, D6
Password Generator Generate strong, random passwords with custom length and character sets. Calcula
Subnet Calculator Calculate network address, broadcast address, subnet mask, and number of usable
Random Name Picker Pick random winners or entries from a list. Select one or multiple names fairly
Sleep Quality Calculator Calculate your sleep quality score, total sleep time, and number of sleep cycles
Bra Size Calculator Find your correct bra size in US and UK sizing from your band and bust measureme
Carbon Footprint Calculator Calculate your annual carbon footprint from driving, flights, and home energy us
Coin Flip Flip a virtual coin online. Simulate single or multiple coin tosses with fair 50
Tip Split Calculator Split a restaurant bill with tip among friends. Calculate each person's share wi
Age Difference Calculator Calculate the age difference between two people in years, months, and days.
Screen Time Calculator Calculate your total daily screen time across devices. See weekly and yearly tot
Word Counter & Text Statistics Estimator Enter a word count to calculate reading time, speaking time, page count, and rea
EV Savings Calculator Calculate how much you save driving an EV vs a gas car. Compare annual fuel cost
Ring Size Calculator Convert finger circumference or diameter to ring sizes in US, UK, EU, and Japan/
Electricity Bill Calculator Calculate your total monthly electricity bill from overall kWh usage with flat,
Unit Price Calculator Compare the price per unit of two or three products to find the best deal. Suppo
Wedding Budget Calculator Plan your wedding budget with recommended allocations, vendor quotes, guest coun
Road Trip Cost Calculator Calculate the total cost of a road trip including fuel, hotels, food, tolls, par
Electricity Usage Calculator Calculate monthly electricity usage and cost by inventorying all your appliances
Grading Scale Calculator Convert raw scores to letter grades and GPA points using standard, custom, or cu
Aspect Ratio Calculator Calculate the aspect ratio of any image or screen from its width and height. Fin
PPI Calculator Calculate pixels per inch (PPI) for any screen from its resolution and diagonal
Dog Food Calculator Calculate how much to feed your dog based on weight, age, and activity level. Ge
AI Cost Calculator Estimate your monthly AI API costs for GPT-4o, Claude Opus, Gemini Pro, and othe
EV Charging Cost Calculator Calculate the cost to charge your electric vehicle at home or at public DC fast
Lawn Fertilizer Calculator Calculate how many pounds and bags of fertilizer your lawn needs based on area,
Pool Chemical Calculator Calculate how much chlorine, pH balancer, alkalinity increaser, and shock treatm
Firewood Calculator Calculate how many cords of firewood you need for the heating season. Compare wo
Cat Age Calculator Convert your cat's age to human years using the AAHA-adjusted formula. Find your
Recipe Scaler Scale any recipe up or down instantly. Enter original and target servings to get
Readability Calculator Check text readability with Flesch Reading Ease, Flesch-Kincaid Grade Level, Gun
DPI Calculator Calculate print size from image resolution and DPI. Find required pixels for any
Shipping Cost Calculator Estimate shipping costs for USPS, UPS, and FedEx based on package weight, dimens
Irrigation Calculator Calculate how many sprinkler heads you need, total GPM flow rate, weekly water u
Grass Seed Calculator Calculate how many pounds of grass seed you need for a new lawn, overseeding, or
Propane Calculator Calculate propane tank fill cost, BTU capacity, monthly usage by appliance, and
Fabric Calculator Calculate how many yards of fabric you need for curtains, dresses, quilts, and u
Dog Pregnancy Calculator Calculate your dog's estimated due date based on mating date. Track canine pregn
Caffeine Intake Calculator Calculate your daily caffeine intake from coffee, tea, and energy drinks. Check
Aquarium Volume Calculator Calculate your aquarium volume in gallons and liters, water weight, heater watta
Sourdough Hydration Calculator Calculate sourdough dough hydration percentage, total flour and water including
Electric Bike Range Calculator Calculate your e-bike range in miles and km from battery capacity (Wh), assist l
Snow Removal Calculator Estimate snow removal time and cost for your driveway or walkway. Compare shovel
BPM Calculator Calculate BPM from beats counted over time, convert BPM to note durations in mil
Tap Tempo Calculator Find the BPM of any song by counting beats over a timed interval. Get the neares
Note Frequency Calculator Convert musical notes to frequency in Hz using equal temperament. Look up any MI
Guitar String Tension Calculator Calculate guitar string tension in pounds using string gauge, scale length, and
Capo Position Calculator Find the guitar capo fret to play in any key using open chord shapes. Look up th
Chord Transposer Transpose guitar chord progressions up or down by semitones or to a target key.
Metronome Calculator Calculate measure duration, beat intervals, subdivisions, and polyrhythm timing
Song Key Calculator Determine the musical key and mode from a chord progression. Get Roman numeral a
Guitar Fret Spacing Calculator Calculate exact fret positions from nut using scale length. Essential for guitar
Reverb Time Calculator (RT60) Calculate room RT60 reverb time using the Sabine equation. Enter room volume and
Lorem Ipsum Generator Generate lorem ipsum placeholder text instantly. Choose number of paragraphs, wo
Slug Generator Convert any title or phrase into a clean URL slug. Supports hyphen and underscor
Case Converter Convert text between all common cases: UPPERCASE, lowercase, Title Case, Sentenc
Regex Tester Test and debug regular expressions online. Find matches, use common patterns (em
Word Frequency Counter Count the frequency of each word in your text. Find top N most common words, ana
Speech Time Calculator Calculate speech and presentation duration from word count. Enter WPM speaking p
Flesch-Kincaid Calculator Calculate Flesch Reading Ease Score (FRES) and Flesch-Kincaid Grade Level (FKGL)
SMOG Readability Calculator Calculate SMOG grade level using the Simple Measure of Gobbledygook formula. Pre
Text Diff Calculator Compare two texts and find differences. Get word-level, character-level, and lin
UUID Generator Generate UUIDs (Universally Unique Identifiers) online. Supports UUID v4 (random
Pizza Dough Calculator Calculate exact pizza dough ingredients by weight for Neapolitan, New York, or D
Yeast Conversion Calculator Convert between instant, active dry, and fresh yeast by weight. Includes sourdou
Baker's Percentage Calculator Convert baker's percentages to ingredient weights or reverse-calculate percentag
Smoking Meat Time Calculator Calculate smoking times and internal temperature targets for brisket, pork shoul
Turkey Cooking Time Calculator Calculate turkey roasting time by weight for 325°F, high-heat, or spatchcock met
Brine Calculator Calculate the exact salt amount for wet brine (5%), dry brine (1%), or equilibri
Sous Vide Time & Temperature Calculator Get sous vide water temperature and cook time for steak, chicken, pork, fish, an
Coffee Ratio Calculator Calculate the perfect coffee-to-water ratio for drip, pour over, French press, A
Espresso Ratio Calculator Calculate espresso brew ratio (yield ÷ dose) for ristretto, normale, or lungo. I
Meal Prep Portion Calculator Calculate total ingredients for batch meal prep by calories and macros. Enter me
Poker Odds Calculator Calculate poker win probability from outs using the rule of 2 and 4. Get pot odd
Parlay Calculator Calculate parlay combined odds, total payout, and expected value for 2–10 legs.
Implied Probability Calculator Convert American, decimal, or fractional betting odds to implied probability %.
Odds Converter Convert betting odds between American (+150/−110), decimal (2.50), fractional (3
Roulette Payout Calculator Calculate roulette payouts for every bet type (straight 35:1, split 17:1, street
Blackjack Strategy Calculator Get the optimal blackjack basic strategy action (hit/stand/double/split) for any
Lottery Odds Calculator Calculate lottery jackpot odds using C(n,k) combinations. Includes Powerball (1
Bingo Card Generator Generate 75-ball (5×5, B-I-N-G-O) and 90-ball British bingo cards. Calculate pro
Flight Time Calculator Calculate flight time from distance and aircraft cruise speed with wind correcti
Flight Distance Calculator Calculate great-circle flight distance between any two points using coordinates,
Jet Lag Calculator Estimate jet lag recovery time and get an optimal light-exposure and melatonin s
Layover Time Calculator Calculate layover duration and check if your connection meets minimum connection
Luggage Volume Calculator Calculate luggage linear inches and volume in liters. Check compliance with airl
Car Rental Cost Calculator Calculate total car rental cost including taxes, airport surcharges, CDW/LDW ins
Hotel Cost Per Night Calculator Calculate the true hotel cost per night including taxes, resort fees, parking, a
Toll Cost Calculator Estimate toll road costs by distance and per-mile rate, with E-ZPass transponder
Final Grade Calculator Calculate the exam score you need to reach your target course grade. Enter your
Semester GPA Calculator Calculate your GPA for the current semester from your course grades and credit h
Weighted GPA Calculator Calculate your weighted GPA on the 5.0 scale using AP, Honors, and IB courses. C
SAT Score Calculator Calculate your SAT composite score from raw section scores. See your percentile
ACT Score Calculator Calculate your ACT composite score from section raw scores. See your percentile
MCAT Score Calculator Calculate your MCAT composite score from four section scores (472–528). See your
LSAT Score Calculator Calculate your LSAT score (120–180) from section raw scores. See your percentile
Study Time Calculator Calculate how many hours you need to study based on pages to read, practice prob
Exam Curve Calculator Calculate your curved exam grade using three methods: highest-score-equals-100,
Class Rank Percentile Calculator Convert your class rank to a percentile (top X%). Compare rank across school siz
Pizza Per Person Calculator Calculate exactly how many pizzas you need for your group. Enter guest count and
Drinks Per Person Calculator Calculate exactly how many drinks you need for any party or event. Enter guest c
Cake Serving Calculator Find out exactly what size cake you need for your party or wedding. Round, sheet
Tip Jar Split Calculator Split a restaurant tip pool fairly among staff by hours worked, position weight
Dog Walker Rate Calculator Calculate recommended dog walking rates for 20, 30, or 60-minute walks. Adjust f
Babysitter Rate Calculator Calculate fair babysitter rates based on number of children, location, age group
Lawn Mowing Cost Calculator Estimate lawn mowing costs by square footage, service type, and frequency. Get p
House Cleaning Cost Calculator Estimate house cleaning costs for basic recurring, deep cleaning, and move-in/mo
Moving Truck Size Calculator Find the right moving truck size for your home. Compare 10 ft, 15 ft, 20 ft, and
Storage Unit Size Calculator Find the right storage unit size for your belongings. Compare 5x5 through 10x30
Thanksgiving Food Calculator Calculate exact quantities for a Thanksgiving dinner. Get turkey weight, stuffin
Wedding Guest List Calculator Calculate expected wedding attendance from invites sent using local (80%) and de
Birthday Party Cost Calculator Estimate birthday party costs for kids, teens, and adults. Get a full breakdown
Bitrate Calculator Calculate audio and video file size from bitrate and duration. Compare streaming
Tire Size Calculator Decode your tire size (e.g. 225/65R17) to find overall diameter, circumference,
Gear Ratio Calculator Calculate gear ratio, output RPM, and torque multiplication for single-stage, mu
Engine Displacement Calculator Calculate engine displacement in cc, liters, and cubic inches from bore, stroke,
Torque to Horsepower Calculator Convert torque and RPM to horsepower using HP = Torque × RPM / 5252. Also conver
Compression Ratio Calculator Calculate engine compression ratio from swept volume and combustion chamber size
Checksum Calculator Compare MD5, SHA-1, SHA-256, and SHA-512 hash algorithms. Learn when each is app
Piston Speed Calculator Calculate mean piston speed (m/s) from stroke and RPM. Find maximum safe RPM, pe
Car Acceleration 0-60 Calculator Estimate your car's 0-60 mph time from vehicle weight and horsepower using a pro
EV Range Calculator Calculate your electric vehicle's real-world range from battery capacity and eff
Cat Food Calculator Calculate how much to feed your cat daily based on weight, life stage, and activ
Horse Weight Calculator Estimate your horse's weight using the Carroll & Huntington heart-girth tape for
Aquarium Stocking Calculator Calculate how many fish your aquarium can safely hold using multiple methods: th
Rabbit Age Calculator Convert your rabbit's age in months to human years. Find their life stage, expec
Bird Age Calculator Convert your pet bird's age to human years by species. Covers parakeets, cockati
Pet Medication Dose Calculator Calculate pet medication doses by weight for dogs, cats, rabbits, and horses. Co
Weighted Grade Calculator Calculate your weighted course grade from assignments, midterms, and finals with