Time Duration Calculator

Find the elapsed time between two clock times, including an overnight period when the end time is earlier.

How to use Time Duration Calculator

1. Enter Start Time, End Time. 2. Plain numbers mean minutes; labelled d, h, min and sec are accepted. Durations are non-negative and a duration day means 24 hours. Static answers round to seconds, with nonzero subsecond values labelled. No holiday calendar or daylight-saving adjustment is applied. Equal clocks give zero. Clock-only inputs cannot identify additional elapsed days. 3. Select Calculate or press Enter from a single-line field. In multiline text fields, Enter inserts a line break. 4. Select Copy result to copy the answer, or Reset to clear the form and result.

Why use this tool?

Use Time Duration Calculator when you need elapsed time. Plain numbers mean minutes; labelled d, h, min and sec are accepted. Durations are non-negative and a duration day means 24 hours. Static answers round to seconds, with nonzero subsecond values labelled. No holiday calendar or daylight-saving adjustment is applied. Equal clocks give zero. Clock-only inputs cannot identify additional elapsed days.

How the calculation works

Elapsed clock difference = end − start; add 24 hours when end is earlier. Plain numbers mean minutes; labelled d, h, min and sec are accepted. Durations are non-negative and a duration day means 24 hours. Static answers round to seconds, with nonzero subsecond values labelled. No holiday calendar or daylight-saving adjustment is applied. Equal clocks give zero. Clock-only inputs cannot identify additional elapsed days.

Example

Worked example: Start Time = "23:30"; End Time = "00:15". Result: 45 min.

Practical tip

Check the time duration input and output convention before reusing the result.