Time Duration Calculator

Calculate the duration between two times in hours, minutes and seconds using the below calculator.

Hour
Minute
Second
Start Time
End Time

What Is a Time Duration Calculator?

A time duration calculator tells you exactly how much time passes between a starting time and an ending time. Instead of counting on your fingers or converting everything to 24-hour format in your head, you enter both times and instantly get the elapsed hours, minutes, and seconds.

Common uses include:

  • Checking the length of a work shift or meeting
  • Timing a commute, workout, or study session
  • Verifying hours before filling out a timesheet
  • Calculating overnight shift lengths that cross midnight

How It Works

Both times are converted to seconds since midnight, subtracted, and formatted back into hours, minutes, and seconds. If the end time is earlier than the start time, 24 hours are added so overnight ranges like 11 PM to 7 AM come out correctly as 8 hours.

Frequently Asked Questions

How do I calculate the duration between two times?

Enter a start time and an end time, and the calculator shows the elapsed time in hours, minutes, and seconds, plus the total in minutes and in seconds.

Does it work for overnight shifts?

Yes. If the end time is earlier than the start time, the calculator assumes the end time is on the next day, so a 10 PM to 6 AM shift correctly shows 8 hours.

Can I use the current time?

Yes. Click the "Now" button next to either field to fill in the current time from your device clock.

How is this different from the time card calculator?

This tool measures a single interval between two times. The time card calculator tracks a whole week of shifts, deducts breaks, and produces a downloadable PDF timesheet.

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