Percentage Calculator
Calculate percentages instantly. Find X% of a number, what percent X is of Y, and percent change between two values.
%
Percentage of Value
—
X is what % of Y —
Percent Change —
Extended More scenarios, charts & detailed breakdown ▾
%
Result
—
Remaining (100% − P%) —
Professional Full parameters & maximum detail ▾
%
Batch Calculation
Batch Results —
Sum of Results —
Min Result —
Max Result —
Step-by-Step % Change
Step-by-Step Solution —
How to Use This Calculator
Enter a Value and a Percentage to find that percentage of the value. Use the Advanced fields to find what percent X is of Y, or to calculate percent change between two values.
Formula
P% of V = (P / 100) × V
X is what % of Y = (X / Y) × 100
% Change = ((New − Old) / |Old|) × 100
Example
15% of 200 = 30 • 30 is 15% of 200 • 80 to 100 = +25% change
Frequently Asked Questions
- Multiply 200 by 0.15, which is 15 divided by 100. So 15% of 200 = 0.15 × 200 = 30. In general, P% of V = (P ÷ 100) × V. For example, 8% of 500 = 0.08 × 500 = 40, and 125% of 80 = 1.25 × 80 = 100. A common mistake is forgetting to divide the percentage by 100 first — entering 15 instead of 0.15 would give 3,000, which is 100 times too large. This calculator handles the conversion automatically, so you just enter the percentage as a whole number.
- Percent change measures how much a value has grown or shrunk relative to its original size. Formula: ((New − Old) / |Old|) × 100. A positive result means an increase; a negative result means a decrease. For example, a price rising from $80 to $100 is a +25% change: (100 − 80) / 80 × 100 = 25%. Going from 100 back to 80 is a −20% change — note that increases and decreases of the same magnitude are not symmetric. Always use the original value as the denominator, not the new one.
- Divide the part by the whole, then multiply by 100. Formula: (Part / Whole) × 100. Example: 30 is what percent of 200? → (30 ÷ 200) × 100 = 15%. Another example: 45 is what percent of 60? → (45 ÷ 60) × 100 = 75%. A common pitfall is reversing the numbers — always put the "part" in the numerator and the "total" in the denominator. If the result is over 100%, the part is larger than the whole, which is valid (e.g., profit can exceed cost).
- Percentage points measure the arithmetic difference between two percentages, while percentage change measures the relative difference. For example, if an interest rate rises from 10% to 15%, that is a 5 percentage-point increase but a 50% relative increase in the rate. Mixing these up is a common error in financial and statistical reporting. When a politician says "approval rose 5 points," they mean percentage points. When a fund says "returns improved 50%," they may mean a 50% relative change from a lower percentage.
- Use the percent change formula: ((New − Old) / |Old|) × 100. If the result is positive, it is an increase; if negative, it is a decrease. Example: sales grew from 400 units to 460 units → (460 − 400) / 400 × 100 = 15% increase. For a decrease example, if a stock fell from $120 to $90 → (90 − 120) / 120 × 100 = −25% (a 25% decrease). Use the absolute value of Old in the denominator when the original value could be negative, to ensure the direction of change is captured correctly in the sign of the result.