Even experts make mistakes. Watch out for:
The relationship between the two is not a simple subtraction of a fixed number because the Shamsi year starts in late March, and the Gregorian year starts in January.
Miladi Year = Shamsi Year + 621 (for Jan–Mar dates)
Miladi Year = Shamsi Year + 622 (for Apr–Dec dates) tarikh shamsi b miladi
Why? Because the Shamsi new year starts around March 20–21.
Because leap years differ (Shamsi is astronomically more precise), use one of these: Even experts make mistakes
To quickly convert near the beginning of the year:
Example A (after March 20):
Example B (before March 20):
The Shamsi calendar (also called the Solar Hijri or Jalali calendar) is used officially in Iran and Afghanistan. The Miladi (Gregorian) calendar is the international standard. To quickly convert near the beginning of the year: