Time Duration Calculator

Find the hours and minutes between any two times — including across midnight.

Reviewed by the WorldCalcs team · Methodology · Last reviewed: June 2026

Duration

8h 30m

Total minutes

510

What is a time duration calculator?

A time duration calculator works out how much time passes between a start time and an end time, shown in hours and minutes (and total minutes). It is useful for timesheets, shifts, cooking and travel.

How it works

The tool converts both times to minutes since midnight, subtracts the start from the end, and converts the result back to hours and minutes. If the end time is earlier than the start, it treats the span as crossing midnight. Example: 09:00 to 17:30 is 8 hours 30 minutes, or 510 minutes.

All calculations happen in your browser. Nothing is sent, stored, or tracked.

Results are estimates and may contain errors — for general information only, not professional advice. Always verify before relying on them. Disclaimer

How to use

Enter a start time and an end time in 24-hour format (HH:MM). The duration is shown in hours and minutes, plus the total in minutes.

If the end time is earlier than the start time, the calculator assumes the end is on the following day. That makes it perfect for night shifts, overnight travel, or any interval that crosses midnight.

Frequently asked questions

What if the end time is earlier than the start time?+

The calculator assumes the end time is on the next day, so a shift from 22:00 to 06:00 correctly returns 8 hours.

Does it count seconds?+

No. Inputs are in hours and minutes (HH:MM), which is the level of precision needed for shifts, billing, study sessions, and most everyday timing.

Are breaks subtracted?+

No. The duration is the raw time between the two clock times. Subtract any unpaid breaks manually if you need net working hours.

How many minutes are in 8 hours 30 minutes?+

510 minutes (8 × 60 + 30).

How does it handle times that cross midnight?+

If the end time is before the start time, the calculator adds 24 hours, so 22:00 to 01:30 is 3 hours 30 minutes.

Can I get the result in total minutes?+

Yes. The tool shows both hours-and-minutes and the total number of minutes.

Does it include the end minute?+

It measures the gap between the two times, so 09:00 to 09:01 is 1 minute.