Example: Start — hour (24h): 9 h · Start — minute: 15 min · End — hour (24h): 17 h · End — minute: 45 min → Duration: 8 h 30 min.
In decimal hours: 8.5
In minutes: 510
Frequently asked questions
How do I calculate time duration? Enter your numbers above and the result updates instantly. For example: Start — hour (24h): 9 h · Start — minute: 15 min · End — hour (24h): 17 h · End — minute: 45 min → Duration: 8 h 30 min.
Is this Time Duration Calculator free? Yes — completely free with no sign-up or paywall. It runs entirely in your browser and keeps working offline; the numbers you enter never leave your device.
How accurate is it? It uses the standard published formula for time duration. Results are estimates for planning — not financial, tax, medical, engineering, or legal advice.