Time Calculator (Add & Subtract Hours, Minutes, Seconds)
Add or subtract hours, minutes and seconds, find the time between two clock times, or add time to a clock time.
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Time Calculator adds and subtracts durations in hours, minutes and seconds, and shows the answer as hours and minutes and as decimal hours.
More about Time Calculator (Add & Subtract Hours, Minutes, Seconds)How to use, good to know & FAQ
Three ways to calculate time
- Add or subtract durations: add up lap times, video clips, workouts or several work sessions.
- Time between two clock times: find how long something lasted. Overnight times work too.
- Add time to a clock time: find what time it will be 3 hours 45 minutes after 10:30 AM, or what time it was 90 minutes ago.
How to use Time Calculator
- Choose what you want to calculate.
- Fill in the hours, minutes and seconds (or the start and end times).
- Add more rows with the + button if you need them.
- The result updates as you type.
Good to know
- Decimal hours are handy for timesheets and invoices: 7 h 30 min is 7.5 hours.
- Minutes and seconds above 59 are fine; 90 minutes is counted as 1 h 30 min.
- For a full week of shifts with breaks and overtime, the Working Hours Calculator is the better fit.
Frequently asked questions
How do I add hours and minutes together?
Add the minutes first. If they come to 60 or more, carry one hour for every 60 minutes, then add the hours. 2 h 45 min + 1 h 30 min = 4 h 15 min.
How do I convert minutes to decimal hours?
Divide by 60. 20 minutes is 0.33 hours and 45 minutes is 0.75 hours.
How many hours are between 10 PM and 6 AM?
8 hours. When the end time is earlier than the start, the calculator counts it as the next day.
When to use Time Calculator
For timesheets, study and workout logs, video editing, cooking and travel plans, or any time you need to add up time without doing base-60 maths in your head.
Related: Need a weekly timesheet with overtime? Try the Working Hours Calculator.