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# Calendar converter

Convert a date between the Gregorian calendar and fourteen others — Hijri, Hebrew, Persian, Indian national, Coptic, Ethiopic, Chinese, Japanese eras and more — using your browser's own ICU tables, in both directions.
ICU via Intl · both directions · supported range 1900–2100ClearGregorian → other calendarsOther calendar → GregorianGregorian date

today is taken from your browser after the page loads

Converted by your browser's own ICU calendar tables via Intl (UTC calendar days; time zones never enter). Reverse direction: a bounded binary search over the supported 1900–2100 Gregorian range, verified by formatting back — no match means no such date, never a nearest guess.

- Conversions are calendar days at UTC — time zones and DST never enter a calendar conversion. Instants belong to the sky and timezone tools.
- The supported range is exactly 1900–2100 Gregorian. Outside it the tool refuses; inside it, every reverse conversion is verified by formatting back before it is shown.
- Calendars this browser’s ICU does not provide are absent from the list — probed live, never assumed.
- Hijri months in particular depend on authority (sighting vs table); the three Hijri variants here are the table-based ones ICU ships, and their labels say which is which.
Nothing in yet

Paste, drop, or type to begin. Everything stays on this device.

your browser’s ICU tables do the converting; the reverse search is bounded and verified

## Next door in Time

- [Date math](/time/date-math)
- [Sunrise & sunset](/sky/sunrise-sunset)
[All time tools](/time)

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Canonical HTML: https://nutter.tools/time/calendar-converter
Markdown version: https://nutter.tools/time/calendar-converter/index.md
Plain-text version: https://nutter.tools/time/calendar-converter/index.txt
Agent index: https://nutter.tools/llms.txt