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Time Duration Calculator
Add and subtract durations like 1:20:00 and 45m, convert to decimal hours, and find the time between two clock times.
Free, no uploads, no sign-up. Runs 100% in your browser.
How Time Duration Calculator works
Worked out in your browser with your device clock and time zone. Calendar files follow the iCalendar standard (RFC 5545), so Google, Apple and Outlook all open them.
Input: Text. Output: Text.
How to use Time Duration Calculator
- Type one duration per line.
- Read the total in every format.
- Use Convert or Time between for single values.
Tips
- Times use your device time zone. Calendar files store times in UTC, so everyone sees their own local time.
- ICS files open in Google Calendar, Apple Calendar and Outlook.
Time Duration Calculator FAQ
- Are my files uploaded?
- No. This tool runs entirely in your browser tab. Files are read from your disk into memory and the result is generated locally.
- Is it free? Are there limits or watermarks?
- Free and open source (MIT). There are no file-size caps, daily quotas, accounts or watermarks.
- Does it work offline?
- Yes, once the page (and any engine it needs) has loaded, it keeps working without a connection thanks to the service worker cache.
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