Time Duration Calculator
Convert a duration in hours, minutes, and seconds into total seconds, decimal hours, and minutes. Useful for billing and time tracking.
Total Seconds
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Total Minutes —
Decimal Hours —
Normalized —
Extended More scenarios, charts & detailed breakdown ▾
Total Seconds
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Total Minutes —
Decimal Hours —
Professional Full parameters & maximum detail ▾
Normalized HH:MM:SS
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Total Seconds —
Total Minutes —
Decimal Hours —
Billable Amount ($) —
Tax Amount ($) —
Total with Tax ($) —
How to Use This Calculator
- Enter the hours, minutes, and seconds of the duration.
- Results instantly show total seconds, total minutes, and decimal hours.
- All fields accept values beyond the normal range (e.g., 90 minutes).
Formula
Total seconds = h × 3600 + m × 60 + s
Decimal hours = Total seconds ÷ 3600
Total minutes = Total seconds ÷ 60
Example
Example: 1h 45min 30sec → Total seconds: 6330, Total minutes: 105.5, Decimal hours: 1.758.
Frequently Asked Questions
- Divide the minutes by 60 and add to the whole hours: Decimal hours = hours + (minutes ÷ 60). For example, 2 hours 30 minutes = 2 + 30/60 = 2.5 decimal hours. Another example: 4 hours 45 minutes = 4 + 45/60 = 4.75 hours. If seconds are involved, also add seconds ÷ 3600. For example, 1 hour 20 minutes 30 seconds = 1 + 20/60 + 30/3600 = 1.3417 decimal hours. Decimal hours are the standard format for payroll, project billing, and time-tracking software because they allow direct multiplication by an hourly rate without any unit conversion.
- Total seconds = (hours × 3600) + (minutes × 60) + seconds. Each hour contains 3,600 seconds (60 minutes × 60 seconds), and each minute contains 60 seconds. For example, a duration of 2 hours 15 minutes 45 seconds = (2 × 3600) + (15 × 60) + 45 = 7,200 + 900 + 45 = 8,145 seconds. Knowing the total seconds is useful when calculating average speeds (distance ÷ total seconds), data transfer rates (bytes ÷ total seconds), or when programming time delays. You can also reverse this: from 8,145 total seconds, floor(8145 ÷ 3600) = 2 hours, floor((8145 mod 3600) ÷ 60) = 15 minutes, 8145 mod 60 = 45 seconds.
- Yes — the calculator accepts any non-negative value for hours and minutes. Entering 90 minutes is the same as entering 1 hour 30 minutes, and the calculator normalizes the output accordingly. This is convenient when working with raw data where durations may be expressed entirely in minutes — for example, a 145-minute meeting is 2 hours 25 minutes, and you can enter 0 hours and 145 minutes without having to pre-convert. The seconds field is limited to 0–59 for consistency. The normalized display at the bottom always shows the result in standard HH:MM:SS format, confirming how the input was interpreted.
- Take the integer (whole) part as the hours, then multiply the fractional decimal part by 60 to get the minutes. For example: 3.25 hours = 3 hours + (0.25 × 60) = 3 hours 15 minutes. Another example: 7.833 hours = 7 hours + (0.833 × 60) = 7 hours 50 minutes. For seconds, multiply the remaining decimal after extracting minutes by 60 again: 1.5042 hours = 1 hour + (0.5042 × 60) = 1 hour 30.25 minutes = 1 hour 30 minutes 15 seconds. This reverse conversion is needed when you calculate a decimal result (such as from dividing total work time) and need to display it as a time on a clock or timesheet.
- Yes — the decimal hours output can be multiplied directly by an hourly rate to get a billable amount. For example, if you worked 2 hours 45 minutes (2.75 decimal hours) and your rate is $85/hour, your invoice is 2.75 × $85 = $233.75. This is faster and less error-prone than trying to convert $85 ÷ 60 = $1.4167/minute and then multiplying by 165 minutes. Most time-tracking tools like Toggl, Harvest, and FreshBooks also display time in decimal hours for exactly this reason. Use the decimal hours result directly when filling in timesheet systems or calculating project costs across multiple team members at different rates.