Time duration calculator
Work out how long there is between a start and end time — handling shifts that run past midnight and subtracting a break — as hours & minutes, decimal hours and total minutes. Fully offline.
Open Time duration calculator →What is the time duration calculator?
A simple tool that works out how long there is between a start time and an end time — including shifts that run past midnight — and subtracts a break if you have one. It shows the result as hours and minutes, decimal hours and total minutes. It runs entirely in your browser and works offline.
How to use Time duration calculator
- Enter the start time — Type or pick the time you started in the Start time field.
- Enter the end time — Set the End time. If it's earlier than the start, the tool counts it as the next day and flags it as an overnight shift.
- Add a break — Optionally enter your break in minutes — it's subtracted from the total to give the net worked time.
- Read the result — See the duration as hours and minutes, plus decimal hours and total minutes, all updating live as you change the inputs.
Frequently asked questions
Does it handle overnight shifts?
Yes. If the end time is earlier than the start time, it's counted as the following day and a note confirms the overnight shift.
What are decimal hours used for?
Decimal hours express the duration as a single number, like 7.5 instead of 7h 30m. Many payroll and invoicing systems expect time in this format.
How does the break affect the total?
Any minutes you enter as a break are deducted from the gross time, so the figures shown are the net time actually worked.
Is my data saved or uploaded?
No. The calculation happens entirely in your browser — nothing you type is sent anywhere, and the tool keeps working offline.
Tips
- Use decimal hours when entering time into payroll or invoicing software.
- Leave the break at 0 if you want the full gross duration between the two times.
- For a whole week of shifts and pay, use the timesheet calculator instead.