The Solar Hijri Calendar: What It Is and How It Differs From the Lunar

Hijri calendar · 3 min read · Last updated: 2 November 2026

If you see a date such as “1405” on an Iranian document, you might take it for a wrong Hijri date, since the current Hijri year is 1448. In fact it is a solar Hijri date: a different calendar that shares only its starting point with the lunar Hijri calendar. This article explains the difference so you do not mix them up.

A shared starting point

Both calendars count years from the Prophet’s ﷺ Hijra in 622. But the lunar calendar counts lunar years (354 or 355 days) and the solar calendar counts solar years (365 or 366 days). Because the lunar year is about eleven days shorter, the gap has built up over the centuries, and today the lunar calendar is about 43 years ahead.

How does the solar calendar work?

• The year begins at the spring equinox, on 20 or 21 March, the day of Nowruz.
• The first six months have 31 days, the next five have 30, and the last has 29, or 30 in a leap year.
• The months have Persian names: Farvardin, Ordibehesht, Khordad, Tir, Mordad, Shahrivar, Mehr, Aban, Azar, Dey, Bahman, Esfand.

For example, the solar year 1405 began on 21 March 2026, while the lunar year 1448 began on 16 June 2026 according to Umm al-Qura.

Where is it used?

The solar Hijri calendar has been the official calendar of Iran since the 1920s. It was also official in Afghanistan until the authorities there switched government correspondence to the lunar calendar in 2022. Religious occasions such as Ramadan and the two Eids are still calculated in Iran itself with the lunar calendar, since they are tied to the lunar months.

Comparison table

What does hijriGO use?

The site uses only the lunar Hijri calendar, according to Umm al-Qura, and does not convert to the solar calendar. If your date is solar, do not enter it in our converter: the result would be wrong. For our method, read Method & data source, and for the comparison with the Gregorian calendar, Hijri vs Gregorian calendar.

Common questions

How can I tell whether a date is solar or lunar?

The clearest sign is the year number: in 2026 the solar year is 1404 or 1405, and the lunar year 1447 or 1448. There are also the month names: Persian (Farvardin, Mehr, Dey…) for solar, Arabic (Muharram, Ramadan, Shawwal…) for lunar.

Why do religious occasions move in the Iranian solar calendar?

Because Ramadan, the two Eids and Ashura are tied to the lunar months, so they move about eleven days earlier each year in any solar calendar, whether solar Hijri or Gregorian. Calendars printed in Iran therefore show both dates.

Is Nowruz a religious occasion?

Nowruz is the Persian solar new year, tied to the spring equinox. It is a traditional and cultural festival in Iran and other countries, not one of the Islamic events the site covers.

How can I roughly convert a solar year to a Gregorian year?

A useful rule of thumb: from 1 Farvardin (around 21 March) to around 10 Dey, add 621 to the solar year number; from around 11 Dey to the end of Esfand, add 622. For example, Farvardin 1405 falls in March and April 2026, while Bahman 1405 falls in January and February 2027. An exact day-by-day conversion needs a table or a specialist solar calendar tool.

Will the site add a solar converter?

For now we focus on the lunar Hijri calendar according to Umm al-Qura, the one used for worship and the one most of our visitors need. If you have a specific need for solar dates, write to us from the contact page.

In short

• Lunar Hijri: 354 or 355 days, months that move through the seasons, the calendar of worship.
• Solar Hijri: 365 or 366 days, starting at the spring equinox, the official calendar of Iran.
• Both count from the Hijra; the gap between their year numbers is now about 43 years.