Time Calculator
Add or subtract hours, minutes, and seconds. Calculate duration between two times. Enter values in any combination — the calculator handles overflow and conversion automatically. 100% browser-based.
How the Time Calculator Works
This time calculator lets you add or subtract time durations expressed in hours, minutes, and seconds. It converts everything to total seconds internally, performs the arithmetic, then converts back to a readable hours:minutes:seconds format. The calculator handles overflow automatically — for example, 75 minutes becomes 1 hour and 15 minutes.
You can use this for calculating total work hours, adding up exercise durations, figuring out cooking times, computing travel durations, or any situation where you need to add or subtract time values. Enter the first time, choose add or subtract, enter the second time, and get your result instantly.
Time Calculation Method
Total Seconds = (Hours × 3600) + (Minutes × 60) + Seconds
Result = Time 1 Total Seconds ± Time 2 Total Seconds
Hours = floor(Result / 3600), Minutes = floor(Remainder / 60), Seconds = Remainder
Where:
- 3600 = seconds in one hour
- 60 = seconds in one minute
- Negative results are shown with a minus sign
Example Calculations
Example 1: Add Two Work Shifts
Morning shift: 4 hours 30 minutes + Afternoon shift: 3 hours 45 minutes
- Time 1: 4h 30m 0s = 16,200 seconds
- Time 2: 3h 45m 0s = 13,500 seconds
- Total: 29,700 seconds = 8 hours 15 minutes 0 seconds
Example 2: Subtract Break Time
Total shift: 8 hours 0 minutes − Lunch break: 0 hours 45 minutes
- Time 1: 8h 0m 0s = 28,800 seconds
- Time 2: 0h 45m 0s = 2,700 seconds
- Result: 26,100 seconds = 7 hours 15 minutes 0 seconds
Example 3: Add Race Lap Times
Lap 1: 1 minute 32 seconds + Lap 2: 1 minute 28 seconds
- Time 1: 0h 1m 32s = 92 seconds
- Time 2: 0h 1m 28s = 88 seconds
- Total: 180 seconds = 0 hours 3 minutes 0 seconds
Common Uses for Time Calculation
Time calculators are used daily by employees tracking work hours, runners adding lap times, cooks combining recipe preparation and cooking durations, project managers estimating task completion, students calculating study time, and travelers adding flight durations with layovers. Any scenario where you need to combine or compare time durations benefits from a simple time calculator.
Time Conversion Reference
For quick reference: 1 hour = 60 minutes = 3,600 seconds. 1 day = 24 hours = 1,440 minutes = 86,400 seconds. 1 week = 168 hours. When the result exceeds 24 hours, this calculator shows the total hours (e.g., 26 hours 15 minutes) rather than converting to days, which is more practical for most use cases.