Time Duration Calculator

Enter a start and end date-time to get the duration in days, hours and minutes, plus totals in each unit.

Start

End

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🔒 Nothing you enter is sent anywhere or stored. All processing happens in your browser.

How it works

Enter a start date and time and an end date and time, and the tool measures the exact span between them. The headline result breaks the duration into days, hours and minutes — for example "2d 5h 30m" — which is the natural way to read a gap that runs across one or more days.

Below that, you also get the total in each unit: the same duration expressed entirely in days, entirely in hours, and entirely in minutes. That's handy when you need a single number — total hours for a timesheet, or total minutes for billing — rather than a mixed breakdown.

Overnight and multi-day spans are handled automatically, and if you accidentally put the end before the start, the tool still shows the size of the gap and flags the order rather than failing. Everything is computed in your browser, so your schedule stays private.

Examples

Shift from 9:00 to 17:30 → 8h 30m (8.5 total hours).

A trip from Fri evening to Sun afternoon → the exact days, hours and minutes.

Two timestamps in a log → total minutes elapsed between them.

Frequently asked questions

What formats can I enter?

Use the date-and-time pickers for both the start and end. They capture the calendar date and the time of day together.

What if the end is before the start?

The tool still shows the size of the gap and adds a note that the end came before the start, so you can fix the order if it was a mistake.

Does it account for days rolling over?

Yes. Multi-day and overnight spans are handled correctly, and the breakdown carries hours and minutes over into days as needed.

Why show totals as well as a breakdown?

The breakdown (days, hours, minutes) reads naturally, while the totals give you one figure — like total hours — for timesheets or billing.

Is my data private?

Yes. All calculations happen in your browser and nothing you enter is stored or uploaded.