Time Duration Calculator

Calculate hours and minutes between two times. Includes decimal hours for timesheets.

Last updated: April 2026 · Source: National Physical Laboratory — Time

Start Time

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→

End Time

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Duration

8h 30m

510 minutes · 8.50 decimal hours

Disclaimer

This calculator is provided for informational purposes only and should not be considered as financial or tax advice. All calculations are performed locally in your browser — no personal data is collected or sent to our servers. Rates and thresholds are sourced from HMRC and GOV.UK and are updated for the current tax year. Always verify results with HMRC or consult a qualified professional before making financial decisions.

How It Works

This calculator finds the duration between two times in hours, minutes and seconds. It handles overnight spans that cross midnight correctly. You can also add or subtract a duration from a start time to find the end time.

The tool is useful for calculating shift lengths, journey times, cooking durations and billable hours. Enter times in either 12-hour (am/pm) or 24-hour format. Results are shown in both total minutes and the hours-and-minutes breakdown.

Example: Duration from 09:15 to 17:45

  1. Duration: 8 hours 30 minutes
  2. Total minutes: 510
  3. In decimal hours: 8.50

Source: National Physical Laboratory — Time

Frequently Asked Questions

What does the Time Duration Calculator do?
Calculate hours and minutes between two times. Includes decimal hours for timesheets. All calculations are performed in your browser using official UK rates and thresholds.
Is this calculator free to use?
Yes. All calculators on Calks.uk are completely free to use. No account or registration is required. All calculations run in your browser — no data is collected.
Can I use this on my phone?
Yes. All our calculators are fully responsive and work on smartphones, tablets and desktop computers. The interface adapts to your screen size automatically.