How to use the Time Duration Calculator
- Enter a start and end time (an end earlier than the start means the next day).
- Subtract any break.
- Or list durations to add them up.
Decimal hours
Timesheets and invoices often need decimal hours: 8 h 15 min is 8.25 hours (15 ÷ 60). For a whole week of shifts, use the Time Card Calculator; to track time live, use the Time Tracker.
Also searched as: hours between two times, time calculator, add hours and minutes, hours calculator, time difference calculator.
Tools that pair well with the Time Duration Calculator
- Date Calculator — Find the date that is a number of days, weeks, months or years before or after another date — with an option to count business days only.
- Online Stopwatch — A precise stopwatch in your browser: start, record laps, see your fastest and slowest lap, and export the lap times.
- Salary to Hourly Calculator — Turn a yearly salary into an hourly rate — or an hourly wage into a salary — and see the daily, weekly, biweekly, monthly and yearly equivalents, adjusted for your hours and unpaid time off.
- Roman Numeral Converter — Convert any number from 1 to 3,999,999 into Roman numerals — or read Roman numerals back as numbers — with a breakdown of every symbol.
Frequently asked questions
How do I calculate an overnight shift?
Enter an end time earlier than the start, such as 22:00 to 06:00; it is counted into the next day.
How do I convert minutes to decimal hours?
Divide by 60: 45 minutes is 0.75 hours.
Is anything I enter saved or sent?
No. The calculation runs in your browser. Your last inputs are remembered on this device only, so the page opens where you left off.
Can I install Time Duration Calculator as a web app and use it offline?
Yes. Time Duration Calculator is an installable web app (PWA) — installed from your browser, not downloaded from an app store. Click Install app at the top of this page in Chrome or Edge (Windows, macOS, Linux, ChromeOS) or on Android, use Share → Add to Home Screen on iPhone and iPad, or File → Add to Dock in Safari 17+ on a Mac. It then opens in its own window with its own icon, and because it runs entirely in your browser it keeps working offline. Firefox on desktop can’t install web apps. How installing works.