Multi-Calendar Converter
Pick any Gregorian date and instantly see the equivalent in ten of the world's most-used calendar systems — Hijri, Hebrew, Persian, Buddhist, Japanese, Indian, Coptic, Ethiopic and more.
Conversions
Calendars at a glance
| Calendar | Used in | Year offset vs. Gregorian |
|---|---|---|
| Gregorian | Most countries (civil) | — |
| Hijri (Islamic) | Saudi Arabia, Islamic religious life | Lunar — ~11 days shorter per year |
| Hebrew | Israel (religious & civil) | +3760 years |
| Persian (Jalali) | Iran, Afghanistan | −621 years |
| Buddhist (Thai) | Thailand, parts of SE Asia | +543 years |
| Japanese | Japan (uses imperial eras) | Era-based, e.g. Reiwa 8 |
| Indian National | India (official civil) | −78 years |
| Coptic | Egypt (Christian) | −283/284 years |
| Ethiopic | Ethiopia, Eritrea | −7/8 years |
Why a multi-calendar converter?
Most calendar tools focus on one tradition. Date Estimator's converter embraces the diversity of how the world keeps time — useful for international scheduling, religious observances, genealogy and just understanding how a single date is expressed across cultures.
How it works
Modern browsers ship with the Intl.DateTimeFormat API, which supports a long list of calendar systems standardised by the Unicode Consortium (CLDR). The converter formats your selected date using each calendar in turn, with no third-party servers involved.