Persian to Gregorian Converter

Persian ↔ Gregorian conversion

The Persian calendar (Shamsi / Jalali / Solar Hijri) is the official calendar of Iran and Afghanistan. Because it's a solar calendar that begins at the exact moment of the vernal equinox each year, it stays perfectly aligned with the seasons — and converting between Persian and Gregorian is straightforward arithmetic.

How accurate is this converter?

We use the 33-year arithmetic cycle approximation, accurate to within about half a second per year of the true astronomical calendar. For any date in the 20th, 21st, or 22nd century, our conversions match the Iranian government's official calendar exactly.

Nowruz (Persian New Year)

The Persian year begins at Nowruz — the exact moment of the vernal equinox, which falls on 20 or 21 March in most Gregorian years. Some recent and upcoming Nowruz dates:

• Nowruz 1404 — 20 March 2025
• Nowruz 1405 — 21 March 2026
• Nowruz 1406 — 21 March 2027
• Nowruz 1407 — 20 March 2028 (Gregorian leap year)

Persian vs Islamic calendars

Iran uses two different "Hijri" calendars — and they disagree. The Solar Hijri (Persian) is used for civil and government purposes; the Lunar Hijri (Islamic) is used for religious observances. Both count years from the same event (the Hijra in 622 CE), but the Persian year is 1405 while the Islamic year is 1447, because lunar years are shorter.

Key dates in the Persian calendar

Why convert Persian to Gregorian?

• Travel to Iran or Afghanistan — all official dates in both countries are Persian; visa paperwork, flight bookings, and appointments will be listed in Shamsi.
• Iranian diaspora communities — cultural calendars and Persian-language publications use Shamsi dates for Iranian holidays.
• Academic research — 20th-century Iranian history sources are dated in Shamsi.
• Family records — birth certificates, marriage records, and passports from Iran are in Shamsi.

The arithmetic of the 33-year cycle

Persian leap years fall in a 33-year pattern: years 1, 5, 9, 13, 17, 22, 26, 30 within each cycle. This gives 8 leap years in 33 (vs. 8.25 in 33 for the Gregorian 4-year rule), producing a mean year of 365.2424 days — almost exactly the true tropical year of 365.2422 days.

The error is about 0.0002 days per year, or one day every 5,000 years. By comparison, the Gregorian calendar errs by about one day every 3,300 years. The Persian calendar is quietly the most astronomically accurate calendar in widespread civil use today.

Afghan calendar: same structure, different names

Afghanistan uses the same Solar Hijri structure as Iran, but with zodiac-based month names:

Day numbering and length are identical — only the names differ. Both refer to the same day in the same calendar.