Persian Calendar Converter

In short The Solar Hijri calendar — Shamsi in Iran, Jalali in older usage — counts from the same Hijra as the Islamic lunar calendar but follows the sun, so it stays fixed against the seasons rather than drifting eleven days a year. The year begins at Nowruz, on or about 21 March, and the months are regular in a way the Gregorian months are not: the first six have 31 days, the next five have 30, and Esfand has 29 or 30. There is one honest complication. This tool implements the arithmetic calendar, the 2820-year cycle, which is exact, reversible and gives the same answer on every device. Iran's official calendar is astronomical: the year starts on the day the March equinox falls before noon at the reference meridian, and no fixed arithmetic rule reproduces that for every year. Checked against eight published Nowruz dates, seven agreed and 1404 did not. For conversion and record-keeping the arithmetic calendar is what you want; for a legally significant date, check an Iranian source.