ISO 8601 Converter
Convert dates and durations to and from ISO 8601 format.
About the ISO 8601 Converter
Convert between local dates and ISO 8601 date-time strings, and parse or build ISO 8601 durations in the PnYnMnDTnHnMnS format.
Examples
ISO duration
P1Y2M10DT2H30M0SOutput
1 year, 2 months, 10 days, 2 hours, 30 minutesKeyboard shortcuts
- Copy the main outputCtrl / ⌘ + Shift + C
- Download the resultCtrl / ⌘ + S
- Share this toolCtrl / ⌘ + Shift + S
- Reset the inputsAlt + R
- Open the tool search paletteCtrl / ⌘ + K
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Frequently asked questions
Read more
- Timezones, UTC and ISO 8601: dates without bugs
Why 'store dates in UTC' is only half the rule, how ISO 8601 avoids ambiguity, and the daylight saving edge cases that break naive code.
- Timezones and UTC: the developer's survival guide
Why every timestamp bug traces back to the same handful of mistakes, and the rules that make timezone handling boring instead of terrifying.
Version 1.0.0 · Updated 2026-08-06 · Runs entirely in your browser