Time Calculator

Enter a start and end time to see the duration in hours and minutes.

Results

Duration
8 h 45 min
Decimal hours
8.75
Total minutes
525
Total seconds
31,500

Because time runs in sixties, adding and subtracting it is not like ordinary arithmetic: how long is it from 08:30 to 17:15? The calculator works it out and deducts a break if you have one.

There are two ways to use it: find the duration between two clock times, or add or subtract a duration to get a new time. If the end time is earlier than the start, it is taken to be the next day.

How to calculate Time

  1. Choose what to calculate: a duration, an addition or a subtraction.
  2. Enter times on the 24-hour clock (for example 17 and 15).
  3. Read the duration in hours and minutes, decimal hours and total minutes.

Time formula

  • Duration = end time − start time − break
  • Decimal hours = total minutes ÷ 60
  • New time = start time ± duration (on a 24-hour clock)

Time example

A shift from 08:30 to 17:15 is 8 hours 45 minutes, or 8.75 hours. Adding 2 hours 45 minutes to 22:30 gives 01:15 the next day.

Time: common questions

What are decimal hours for?

Multiplying hours and minutes by a pay rate is awkward. 8 hours 45 minutes is 8.75 hours, which can be multiplied directly by an hourly rate.

How do I calculate a night shift?

Enter 22:00 as the start and 06:00 as the end. Because the end is earlier, the calculator counts it as the next day and returns 8 hours.

How do I convert minutes to decimals?

Divide by 60: 15 minutes is 0.25, 30 minutes 0.5 and 45 minutes 0.75 of an hour.