เครื่องคำนวณระยะเวลา

Manually adding up several durations written as hours:minutes:seconds is awkward — 45 minutes + 40 minutes isn't simply "85 minutes" in normal notation. This tool adds and subtracts multiple durations at once, correctly carrying minutes into hours.

How to use it

• Add several durations in a convenient format (like 1:30:00 or 90 min) and the tool totals them instantly.
• Mark individual durations for subtraction to calculate a difference rather than just a sum.
• The result is shown in a readable format (hours:minutes:seconds) as well as a total number of seconds.

Common uses

• Totaling hours worked across several shifts or tasks in a day.
• Calculating the total runtime of a playlist of videos or podcast episodes.
• Comparing actual time spent on a task against a target (by subtracting).

Things to keep in mind

If the sum of subtractions exceeds the sum of additions, the result is shown with a minus sign — handy for seeing a shortfall of hours against a target at a glance.

Unlike the date-difference calculator, this tool works with plain durations (hours, minutes, seconds), not specific calendar dates.