Time Duration Calculator

Find the hours and minutes between a start and end time, including overnight.

How long between two times?

Enter a start time and an end time and this tool tells you exactly how much time has passed, in hours and minutes. It is handy for working out shift lengths, study sessions, cooking times or how long a journey took.

Overnight spans handled for you

If the end time is earlier than the start time, the calculator assumes the period runs past midnight and adds 24 hours automatically — so a shift from 22:00 to 06:00 correctly reads as 8 hours rather than a negative value.

How to use the Time Duration Calculator

  1. Enter the start time. Set when the period began.
  2. Enter the end time. Set when it finished.
  3. Calculate. Read the duration in hours and minutes.
  4. Check overnight spans. If the end is before the start, the tool adds a day for you.

Frequently asked questions

How are overnight periods handled?

If the end time is before the start time, the calculator adds 24 hours, so a span that crosses midnight is measured correctly.

What if the start and end times are the same?

The duration is shown as zero. The tool does not assume a full 24-hour day when the times match.

Does it use a 24-hour clock?

The time fields follow your browser and system settings, which may show a 12- or 24-hour clock, but the calculation is the same either way.

Is anything sent to a server?

No. The duration is worked out entirely in your browser.

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