Convert Jalali (Shamsi) and Gregorian Dates

The Jalali (Shamsi) calendar is the official basis for dates in Iran, and filling a form, writing a contract or agreeing a meeting with someone abroad all require converting it to and from Gregorian. This tool has two tabs: Gregorian to Jalali and Jalali to Gregorian. Input is three plain numbers, year, month, day, and the output is the full date with month and weekday names, so you can check what day of the week, say, 1 Farvardin 1405 falls on. Conversion uses the standard Jalali algorithm built on Julian day numbers, which handles leap years correctly and stays valid far into the future. Everything is computed in the browser and no date is sent anywhere.

This tool runs entirely in your browser. No data is sent to any server.

How to use it

1. 1

   Choose the “Gregorian to Jalali” or “Jalali to Gregorian” tab.

2. 2

   Type the year, month and day into the three boxes.

3. 3

   Read the equivalent date with its month and weekday name in the card below.

Frequently asked questions

Which day is Nowruz each year?

Between 20 and 21 March, depending on the year, which is exactly why the conversion cannot be done mentally. The Jalali algorithm accounts for that shift.

How is a Jalali leap year decided?

The Jalali calendar uses a 33-year cycle rather than the simple every-four-years rule. This tool implements the standard algorithm.

What date range is supported?

The algorithm is correct across several centuries in both directions. Dates outside the calendar’s range return an error.