Time Calculator
Add or subtract two durations in hours, minutes and seconds.
Adding or subtracting durations across hours, minutes, and seconds gets confusing fast once you cross an hour boundary — this handles the carrying and borrowing automatically.
A common use case: work shift totals
If you clocked in at one time and out at another, or need to add up multiple time blocks throughout a day, this avoids the base-60 arithmetic errors that happen when you try to do it by hand.
Frequently asked questions
Can I subtract a larger time from a smaller one?
Yes — the result will show as negative, useful for figuring out how much time remains before a deadline.
Does this handle times over 24 hours?
Yes, this treats time purely as a duration, not a clock time, so totals over 24 hours work correctly for tracking cumulative hours across multiple days.