Time Duration Calculator

Working out hours between two clock times is the kind of arithmetic that looks trivial until a shift crosses midnight or a break has to come off. This calculator handles both, and gives the answer in the two forms people actually need: hours and minutes for a person, and decimal hours for a timesheet or an invoice.

How to use it

1. Enter the start and end times on the 24-hour clock.
2. Enter any break to deduct, in minutes.
3. Read the duration, plus the decimal hours your timesheet wants.

Examples

• 09:30 to 18:00 with a 60 minute break is 7h 30m, or 7.5 decimal hours.
• 22:00 to 06:00 with a 30 minute break is also 7h 30m — the calculator recognises the overnight shift.

Frequently asked questions

How do I calculate hours worked between two times?

Convert both times to minutes since midnight, subtract, and deduct any unpaid break. The awkward part is that clock arithmetic is not ordinary arithmetic — 18:00 minus 09:30 is not 9.30 — which is why doing it by hand so often produces a figure that is out by the minutes column.

How does it handle a night shift past midnight?

If the end time is earlier than the start time, the shift is treated as running into the next day rather than as an error. A 22:00 to 06:00 shift returns eight hours, not a negative number, and the result says plainly that it was read as overnight so you can check the assumption.

Why does my timesheet want decimal hours?

Because payroll multiplies hours by a rate, and 7 hours 30 minutes is 7.5 rather than 7.30. Entering 7.30 into a payroll sheet underpays by eighteen minutes. The calculator gives both figures side by side for exactly this reason.

Should the lunch break be deducted?

If it is unpaid, yes — most salaried and hourly contracts treat a lunch break as unpaid time. Short paid breaks usually stay in. If you are unsure, check the contract, because the difference across a month is roughly a full working day.