Everyday planning

How to calculate the time between two times

A clear method for ordinary time spans, overnight shifts, and time blocks that include breaks.

Updated July 21, 2026 · 3 min read

Start with the complete time span

The duration from a start time to an end time is the full time span, before subtracting breaks or pauses. For example, 08:30 to 17:00 is 8 hours and 30 minutes.

Using a calculator avoids mistakes around the hour boundary. It can also make it easier to compare different schedules consistently.

Handle midnight as a new day

When the end time is after midnight, it belongs to the next day. Add the time from the start until midnight to the time from midnight until the end.

A shift from 21:45 to 05:15 the next day lasts 7 hours and 30 minutes. Marking the next-day setting prevents the calculation from treating the end as earlier than the start.

Subtract breaks separately when needed

A full span does not automatically equal work time, paid time, or study time. Remove unpaid breaks, meal periods, or other gaps after you calculate the total duration.

For attendance, payroll, or a formal schedule, compare the estimate with the applicable policy and recorded times.