Time Calculator: Add, Subtract, and Convert Time in Hours, Minutes, and Seconds
Add or subtract time values, convert between time units, and calculate duration between two times. Handles hours, minutes, seconds, and time across midnight.
How Time Calculations Work
Time is calculated in total seconds and then converted to hours, minutes, and seconds for display.
For times crossing midnight (e.g., 11 PM to 2 AM), the calculator adds 24 hours to the end time before subtracting.
How to Use the Time Calculator
Select calculation mode
Time addition, time subtraction, or time duration between two times.
Enter your time values
Use H:MM:SS format. For duration, enter start and end times.
Click Calculate
See result in hours:minutes:seconds and total minutes/seconds.
Real-World Scenario Example
"A work shift from 9:30 AM to 5:45 PM: duration = 8 hours 15 minutes = 495 minutes = 29,700 seconds."
Inputs
Result
8 hours 15 minutes | 495 minutes | 29,700 seconds
Important Disclaimer
Time calculations are performed in the user's local timezone unless otherwise specified. Results assume a standard 24-hour day. Daylight saving time transitions may affect real-world time duration calculations.
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