Nowruz

Nowruz at a glance

Persian date

1 Farvardin

Gregorian window

March 20 to March 22

Distinct dates

3

Years documented

101

ChinRooz publishes the day the calendar assigns to the new year, not the moment of the equinox.

The first day of the year

Nowruz is the first day of Farvardin, the first month of the Persian solar year, and so the first day of the year itself. It marks the turn of the seasons: winter closes, spring begins in the northern hemisphere, and the calendar starts counting again from the beginning.

It is an old festival, kept far longer than the calendar that now carries it. Nowruz is shared heritage rather than the property of any one country. It is observed across a wide region and beyond it, by communities of many languages and ancestries, by people of several religions and of none, and by families who have carried it with them wherever they have settled.

The shape of the observance varies from place to place and from household to household, but some features are widespread. Homes are cleaned and put in order before the year turns. A table is laid for the new year, arranged with symbolic foods and objects. Then come the visits: relatives and neighbours call on one another over the days that follow, with older members of a family often received first, and the season closes with a day spent outdoors in company. What each of these looks like belongs to the community that keeps it.

Why the year begins where it does

The Persian solar calendar anchors its first day to the vernal equinox — the point in the sun's apparent path when day and night stand in balance and spring opens in the northern hemisphere. The year does not begin on a chosen anniversary. It begins where the sky puts it.

This makes the calendar astronomical in its definition rather than arithmetic. Many calendars are built from a rule: so many days in a month, a leap day inserted on a stated pattern, and the year beginning at whatever point that arithmetic reaches. The Persian year is built the other way round. The equinox comes first, and the calendar arranges itself so that its opening day is the one on which spring has begun.

The consequence is that the day of Nowruz is determined, not decided. No authority selects it and no convention assigns it; it follows from where the earth is in its orbit, and the calendar records the answer. That is also why the twelve months of the Persian year keep such close company with the seasons, month after month, without needing to be corrected back into place.

Why the Gregorian date moves

The equinox does not arrive at the same point in the Gregorian year each time. The Gregorian year is a rule about counting days, and the solar year it approximates is slightly longer than a whole number of them, so the beginning of spring drifts a little forward and is pulled back again by leap days. Seen from the Gregorian side, the equinox wanders within a narrow band, a day or so either side.

Nowruz wanders with it. The Gregorian date of the Persian new year is therefore not one date but a small set of neighbouring dates in late winter and early spring, one of which is far more common than the others. Converting between the two calendars means looking the year up, not applying a fixed offset.

This is why a calendar, a diary, or a piece of software that prints Nowruz on a single fixed Gregorian date is right in most years and wrong in some. The error is quiet and easy to miss, because it is never large — a day early, a day late — and because the common case is common enough to look like a rule. The table below sets out the years the page documents so that the actual Gregorian date can be read off directly for each one.

Why a printed table disagrees

The days Nowruz fell on

Across the 101 years below, Nowruz fell on 3 different Gregorian dates. A printed calendar prints one of them.

1. March 2020 years

2. March 2178 years

3. March 223 years

Nowruz year by year

Every Nowruz this page documents, with the day of the week it fell on.

From March 21, 1950 to March 21, 2050.