Time Duration Calculator

Measure the interval between two clock times.

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Formula / Calculation Method

Duration = end minutes − start minutes; add 1,440 if the end is earlier.

22:00 to 06:00 is 8 hours.

Times use a 24-hour clock. Equal start and end represent zero hours, not a full day.

Measure the interval between two clock times.

Enter start and end times using a 24-hour clock.

Select Calculate after entering your values. Text tools update as you type. Reset restores the starting fields.

An end time earlier than the start means the interval crosses midnight once. The tool reports decimal hours and a whole-hours-plus-minutes breakdown.

Can I calculate an interval longer than 24 hours?

No. This clock-time tool is limited to intervals shorter than one day.

What assumptions does this tool use?

Times use a 24-hour clock. Equal start and end represent zero hours, not a full day.

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