Time calculator

Add or subtract clock durations without carrying errors. Sum billable hours (2h 45m + 3h 30m), subtract break time from shift length, or total segments in hh:mm:ss.

How to add or subtract time

1. Enter first duration in hours, minutes, seconds (or hh:mm:ss).
2. Enter second duration and choose add or subtract.
3. Read total or difference in normalized form.
4. For clock times crossing midnight, use a date-aware tool if needed.

Time calculation examples

Freelance hours

Monday 2h 15m + Tuesday 3h 50m + Wednesday 1h 05m = 7h 20m billable.

Video edit runtime

Three clips: 04:32 + 12:08 + 00:55 = 17:35 total footage before transitions.

Subtract break

8h 00m shift − 0h 45m lunch = 7h 15m paid time (policy-dependent).

When to use the time calculator

• When you total weekly timesheet entries without spreadsheet formulas.
• When you sum podcast or media segment lengths.
• When you plan cooking stages with multiple timed steps.

Duration vs time-of-day

Adding 2h 30m to 11:00 PM yields 1:30 AM next day — a calendar problem. Adding durations 2h 30m + 3h 15m = 5h 45m is pure duration math. Pick the right tool for the question.

Frequently asked questions

Does it wrap at 24 hours?

Duration sums can exceed 24h (e.g. 30h total project time). Clock time mode may wrap differently.

Can I enter decimal hours?

Some tools accept 1.5 h = 1h 30m. Check input mode.

Subtract larger from smaller?

May show negative duration or error — useful for checking overtime balance.

Seconds required?

Optional — leave 0 if you only track hours and minutes.

Difference from working hours calculator?

Working hours often handles start/end clock times and breaks; this tool sums arbitrary durations.