ToolBirch

Time Duration Calculator

Elapsed time between two clock times.Date & Time Tools

Time Duration Calculator

The elapsed time between two clock times. If the end is earlier than the start it is treated as the next day.

Use the picker or type HH:MM.

About this tool

Shift-length maths made safe: if the end time is earlier than the start, it is treated as the next day, so a 23:00 to 01:30 shift correctly reads 2h 30m.

How to use the Time Duration Calculator tool

  1. Enter the two times. HH:MM via the pickers.
  2. Read the duration. Hours and minutes, plus the raw seconds.
  3. Watch the day flag. Cross-midnight spans are labelled.

Supported formats

Input

  • Plain text or file input

Output

  • Converted or analysed output

Inputs are validated before anything is processed. Invalid values and unsupported files are rejected with a clear error instead of failing silently.

Frequently asked questions

How is cross-midnight handled?

Automatically: a negative difference gains 24 hours and the result says so.

Are seconds supported?

The picker supplies HH:MM; the result is minute-precise.

Can I span multiple days?

No — single-day spans only.

Privacy

Everything you enter stays in this browser tab. There is no upload endpoint for tool inputs, no account, and no server-side copy of your text or files. Results are produced locally and disappear when you close the page.

No account is required and no file is ever uploaded. See the privacy policy for details about analytics and the limited data this site stores.

Known limitations

  • Durations longer than 24 hours need the date-based tools instead.

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Time Zone ConverterConvert an instant between IANA time zones.World ClockLive clocks across your chosen cities.Business Days CalculatorCount working days between two dates, skipping weekends and holidays.Countdown TimerLive countdown to any date-time, second by second.