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Time duration calculator

Enter a start and end time to get the exact duration between them.

How Time duration calculator works

Time duration calculates how much time elapses between two times of day, say 09:15 and 17:45, or across midnight (22:00 to 06:30). It gives hours and minutes, a decimal hour value and the total in minutes, so the result fits whatever format your task requires.

This tool focuses on clock times within a day (or overnight). It is different from Date difference, which spans full calendar dates, and from the Timesheet tool, which accumulates multiple clock-in/out pairs into a daily total with pay. If the end time is earlier than the start time it assumes the span crosses midnight, so 22:00 to 06:30 correctly returns 8 h 30 min.

Frequently asked questions

Are the clock times I enter shared with anyone?

No. The subtraction runs entirely in your browser. The start and end times you type are never sent to Sunasty or any third party, they exist only on your device for the duration of your visit.

Does it handle overnight spans (when the end time is before the start time)?

Yes. If the end time is earlier than the start time the tool automatically assumes the span crosses midnight, so 22:00 → 06:30 correctly returns 8 h 30 min.

How is this different from the Timesheet tool?

Time duration answers one question: how long between these two clock times? The Timesheet tool is built for a full working day, it accumulates several clock-in/out entries, deducts breaks, computes daily totals and calculates pay. Use this one for a quick, single duration.

Does it work offline?

Yes, once the page has loaded. Because the processing happens on your device, you can disconnect from the network and the tool keeps working. This is the clearest proof that your data never leaves your machine.

Is it free? Do I need an account?

It is completely free and requires no sign-up. There are no watermarks, no daily limits and no tracking cookies needed to use the tool.