Dates & Time

Time Duration Calculator

Find elapsed time between a start time and end time, including overnight periods.

How to use this time duration calculator

Enter the requested values above and select Calculate. The result updates immediately on the page, so you can change one value and compare different scenarios without leaving the calculator.

Formula and method

Duration = end time − start time; if end is earlier than start, the calculation assumes the end time is on the following day.

Example

9:00 AM to 5:30 PM is 8 hours 30 minutes.

What this calculator is useful for

Find elapsed time between a start time and end time, including overnight periods. It is designed for quick estimates and everyday problem solving. When a calculation affects a contract, tax filing, medical decision or other high-stakes situation, verify the result with the appropriate professional or authoritative source.

Frequently asked questions

What does the Time Duration Calculator calculate?

Find elapsed time between a start time and end time, including overnight periods.

How does the calculation work?

Duration = end time − start time; if end is earlier than start, the calculation assumes the end time is on the following day.

Is this calculator free?

Yes. ERICH Calculators is free to use and no account is required.