Easter dates calculator

The short answer: This Easter dates calculator turns a year into dates: Western (Gregorian) Easter and Orthodox (Julian) Easter. It also calculates movable days like Ash Wednesday, Good Friday, Easter Monday, Ascension and Pentecost. The maths is the Meeus/Jones/Butcher algorithm from Jean Meeus's Astronomical Algorithms (1991), the method church calendars publish from. Below, the guide names every constant behind the number and marks where the arithmetic stops being valid.

Easter is a religious holiday for many of the families reading this. It is also a spring tradition for others; the calendar serves both. Either way, the date is the first domino. School breaks, travel bookings and the big grocery run all hang on it, which is why this tool sits inside our Easter Basket Ideas, Sorted by Who It's For guide.

If you only want the dates themselves, When Is Easter? Dates Through 2032 and Why It Moves lists them plainly. The basket side of the season has its own pages too: what goes in, stuffers by age band, and building one from scratch.

What it computes

Given a starting year, the calculator returns the date of Easter Sunday under either rule, for as many consecutive years as you ask for. It also returns one related day of your choosing: Ash Wednesday, Good Friday, Easter Monday, Ascension or Pentecost. The two calendar rules are computed separately, because they often disagree — in 2027 they land five weeks apart.

How it works

Both rules begin with the same definition: Easter Sunday is the first Sunday after the ecclesiastical full moon that falls on or after March 21. That moon is a calendar construct, fixed by the Gregorian reform of 1582, not a reading of the night sky. The Meeus/Jones/Butcher algorithm turns the definition into plain arithmetic — no moon tables, no observation — and it is the method set out in Jean Meeus's Astronomical Algorithms (Willmann-Bell, 1991, chapter 8).

Older manuals call this machinery the Golden Number and the Epact: where the year sits in the repeating 19-year moon cycle, and the moon's notional age on any date. Meeus's method folds both steps into arithmetic you can run by hand. Orthodox Easter runs the equivalent Julian calculation, then shifts the result into our civil calendar. The conversion adds 13 days, the offset that holds from 1900 to 2099; it becomes 14 days from 2100 (Meeus, 1991, chapter 8).

Each related day is a fixed offset from Easter Day itself. Ash Wednesday falls 46 days before Easter, Good Friday 2 days before, Easter Monday 1 day after, Ascension 39 days after, and Pentecost 49 days after. Those spacings come from the General Roman Calendar's Universal Norms on the Liturgical Year and the Calendar (1969) and the Book of Common Prayer's tables of movable feasts.

Examples

Western Easter from 2027, five years. Set the Gregorian rule from 2027 and the first date returned is Sunday, March 28, 2027 (2027-03-28). The list continues with April 16, 2028; April 1, 2029; April 21, 2030; and April 13, 2031 — five Easters in all.

Orthodox Easter 2027. Run the same year on the Julian rule and Easter falls on Sunday, May 2, 2027 (2027-05-02) — five weeks after the Western date.

Good Friday 2028. Easter 2028 lands on April 16, so Good Friday, two days earlier, falls on Friday, April 14, 2028 (2028-04-14).

Limits

The Gregorian rule holds from the 1582 reform onward, and the Julian conversion only while its offset does — 13 days through 2099, 14 from 2100. Even inside that window the date has edges: the U.S. Census Bureau's Easter dates list, 1600 to 2099, shows Western Easter between March 22 and April 25, never outside them.

One caveat is legal, not mathematical: the Easter Act 1928 (legislation.gov.uk) would fix Easter as the first Sunday after the second Saturday in April, but it has never been brought into force. Until such a law takes effect, the algorithm above is the one the printed calendars follow.