Dates and time
Time duration calculator in UTC
Calculate elapsed time between two UTC dates or timestamps, with days, hours, minutes, seconds and milliseconds.
Runs in your browser. Inputs stay on this page and are not uploaded or added to the URL.
Your result
How to use this tool
Enter a start and end in UTC to calculate elapsed duration. The result reports a days/hours/minutes/seconds breakdown and total duration in several units. An overnight interval needs the actual next date; the tool does not silently roll the clock forward.
UTC timestamps must end with Z. Local civil time zones and their daylight-saving transitions are not inferred. This is elapsed time, not inclusive calendar-day counting, business days or a calendar month calculation. Leap seconds are not represented.
Worked example
From 2026-10-24T09:30:00Z to 2026-10-25T12:45:00Z is 1 day, 3 hours and 15 minutes, or 27.25 hours.
References and method
Contifield is an independent utility site. Reference publishers do not endorse this tool.
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