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Time calculators

Time Calculator

Add or subtract durations in hours, minutes, and seconds.

Time Calculator

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Complete guide

How to use Time Calculator

Enter two durations in hours, minutes, and seconds, choose add or subtract, and the calculator normalizes the result (75 minutes becomes 1h 15m) and shows it in H:MM:SS plus total seconds.

Useful for timesheets, shift lengths, cooking, video editing, and any task where you need to combine elapsed times.

Add or subtract

Pick + to combine two durations or − to find the difference. Negative results are shown with a minus sign.

Automatic normalizing

Enter any values — the calculator rolls 90 seconds into 1m 30s and 80 minutes into 1h 20m for you.

Multiple output formats

Results appear as a readable ‘3h 45m 0s’ and as ‘03:45:00’, plus the raw total in seconds.

Answers

Time Calculator FAQs

How do I add time durations?

Enter the hours, minutes, and seconds for each value, select Add (+), and the result is normalized automatically.

Can I get a negative result?

Yes. If the subtraction goes below zero (e.g. 1:00 − 2:30), the result is shown with a minus sign.

Is this a clock or duration calculator?

It works with durations. To find the gap between two times of day, use the Date Difference Calculator.

How many seconds are in an hour?

3,600 seconds — 60 minutes times 60 seconds.

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