Calculator
Hours and time calculator
Calculate time between clocks, across midnight and after deducting a break. Data is processed only in your browser, and the page explains the formula and limitations of the result.
Reviewed: 3 August 2026Processed locally
Calculator
Enter data
Start and end time, next-day choice and break minutes. Fields marked with an asterisk are required.
How to use the calculator
- Enter the required data: start and end time, next-day choice and break minutes.
- Check the values and select “Calculate”.
- Review the primary result and the detailed calculation components.
Calculation details
Formula and calculation method
Net duration = end time − start time + an optional 24 hours − break duration.
Worked example
From 08:30 to 17:00 with a 30-minute break, net duration is exactly 8 hours.
Limitations
- This is clock arithmetic without dates, zones, daylight-saving changes, employment records or paid-break rules.
Sources
Engine version: 1.0 · Last reviewed: 3 August 2026
Frequently asked questions
Is the entered data sent to a server?
No. The calculation runs locally in your browser and the values are not saved by default.
Is the result definitive?
Not always. This is clock arithmetic without dates, zones, daylight-saving changes, employment records or paid-break rules.