Time Expression Calculator

A calculator where the operands are durations: type 1h 30m + 45m − 0:20 and read the total. Mix formats freely between terms — colon time, unit shorthand, bare minutes — and chain as many + and − as you need.

How to use it

1. 1.Type a duration expression with + and − between terms.
2. 2.Each term can use any format: 1:30, 90m, 1h 15m.
3. 3.Read the result in hh:mm:ss, decimal hours, and minutes.

Questions people ask

Can the result be negative?

Yes — subtracting more than you add yields a negative duration, shown with a minus sign. Useful for “how far behind schedule” questions.

Are multiplication and division supported?

No — terms are durations, and duration × duration has no meaning. To scale a duration, use the playback speed calculator or convert to minutes first.