Time Expression Calculator

Type an expression such as 1d 2h 30m + 45m - 20s and get one normalized duration plus totals in hours, minutes, and seconds.

Time expression

Supported operators are + and −. Duration terms accept d, h, m, s or HH:MM[:SS]. The parser does not use JavaScript eval.

Expression result

—

—HH:MM:SS

—Total hours

—Total minutes

—Total seconds

Ready

Core timing workflows

Start with a direct timer, stopwatch, alarm or focus workflow. Calendar, date arithmetic, clocks and scheduling specialists remain available from the full Date & Time hub.

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How to use this Time Expression Calculator

Type multiple duration terms separated by plus or minus signs. Use d, h, m, and s notation or HH:MM[:SS] for each term.

What the result means

Type an expression such as 1d 2h 30m + 45m - 20s and get one normalized duration plus totals in hours, minutes, and seconds.