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Time Duration Calculator

Enter a start time and an end time to see how long passed, as hours and minutes, decimal hours, minutes and seconds. If the end time is earlier than the start, it is taken to be the next day.

Quick examples

If the end time is earlier than the start, the next day is assumed automatically.

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Duration8 h 45 min
Hours:minutes
8:45
Decimal hours
8.75
Total minutes
525
Total seconds
31,500

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Save a set of inputs you reuse — your usual rate, your loan, your room sizes — and load it back in one tap.

    Your recent calculations

    Results you calculate here are kept on this device so you can come back to them.

      Formula

      Duration = end time − start time (+ 24 h if the end is earlier)
      Decimal hours = minutes ÷ 60

      How to use it

      1. Enter the start time.
      2. Enter the end time.
      3. Add full days in between for spans longer than 24 hours.

      Worked examples

      8:30 am to 5:15 pm

      Hours:minutes
      8:45
      Decimal hours
      8.75
      Total minutes
      525

      11:00 pm to 7:00 am the next morning

      Hours:minutes
      8:00
      Duration
      8 h

      Questions people ask

      How many hours is 8:30 am to 5:15 pm?

      8 hours 45 minutes, which is 8.75 decimal hours.

      How do I work out time across midnight?

      Enter the times as they are. 11:00 pm to 7:00 am is read as 8 hours because the end is assumed to be the following day.

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