Duration to ISO 8601 format
For developers and anyone filling in XML, schema.org or API fields that expect an ISO 8601 duration.
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Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.
How to use it
- Enter years, months, days, hours, minutes and seconds.
- The result appears straight away and updates as you edit.
- Copy the result, or copy a link that keeps the same values to share it.
How it is calculated
Write P, then years Y, months M and days D, then T, then hours H, minutes M and seconds S, leaving out zero parts. A zero duration is PT0S.
Example
Inputs: Years = 0, Months = 0, Days = 1, Hours = 2, Minutes = 30. Result: ISO 8601 duration: P1DT2H30M; Total seconds: 95,400.
Limits and caveats
- Carrying stops at hours and does not roll them into days, since a calendar day is not always 24 hours.
- Weeks (W) are not used here; enter them as days.
Questions about this tool
How do I write 1.5 hours in ISO 8601?
PT1H30M. PT1.5H and PT90M are also valid.
Why does a zero duration show PT0S?
The standard needs at least one component, and PT0S is the usual way to write zero.
Is P1Y always 365 days?
No, a leap year has 366 days, so no total in seconds is given when years or months are set.