WebyTooly

Time calculator

Add or subtract hours, minutes and seconds easily.

Espacio publicitario
Result
4h 15m 0s
Total in minutes
255
Espacio publicitario

How hours, minutes and seconds are added or subtracted

Each duration is first converted to total seconds so it can be used in the calculation:

total seconds = hours × 3600 + minutes × 60 + seconds

The total seconds of both durations are then added or subtracted depending on the chosen operation, and the result is converted back into hours, minutes and seconds:

hours = ⌊seconds ÷ 3600⌋ · minutes = ⌊(seconds mod 3600) ÷ 60⌋ · seconds = seconds mod 60

If the result of a subtraction is negative, the absolute value is shown preceded by a minus sign.

Worked example

Adding 2h 30m 0s and 1h 45m 0s gives 14,400 seconds, equivalent to 4h 15m 0s, or 255 minutes in total.

Frequently asked questions

How do I add hours, minutes and seconds?
Each duration is converted into total seconds (hours × 3600 + minutes × 60 + seconds), the seconds of both durations are added, and the total is converted back into hours, minutes and seconds.
Can I subtract a longer duration from a shorter one?
Yes, if the result is negative the calculator shows it with a minus sign before the resulting hours, minutes and seconds.
What is the 'total in minutes' shown in the result?
It's the resulting duration expressed entirely in minutes (rounding down any leftover seconds), useful for comparing durations quickly.
Can I use decimals in hours, minutes or seconds?
The fields accept numbers, but for accuracy it's best to enter minutes and seconds as whole numbers within their usual range (0-59).

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