Easter is a movable feast. The rule set at the Council of Nicaea and refined over the following centuries says Easter is the first Sunday after the ecclesiastical full moon that falls on or after 21 March. The “full moon” here is not the astronomical one but a value from church tables (the computus), which follow the 19-year Metonic cycle of the Moon. As a result Western Easter always falls between 22 March and 25 April.
Orthodox churches use the same principle but keep the Julian calendar and the older lunar tables. Their Easter therefore lands between 4 April and 8 May in today’s civil calendar. In about a third of years both churches celebrate on the same Sunday (as in 2025 and 2028); otherwise Orthodox Easter is one, four or five weeks later.
The calculator evaluates both algorithms for the year you enter and builds the church year around them: Ash Wednesday 46 days before Easter, Palm Sunday, Good Friday, Easter Monday, Ascension Day (39 days after), Pentecost (49 days after) and Corpus Christi (60 days after).
How to use the Easter Date Calculator
- Year
Results update as you type, every field has its own unit menu, and everything is calculated in your browser.
How it works
Enter a year. The Western date comes from the anonymous Gregorian algorithm (Meeus/Jones/Butcher); the Orthodox date comes from Meeus’ Julian algorithm converted to the Gregorian calendar by adding the century difference (13 days from 1900 to 2099).
Worked example
For 2027: a = 13, b = 20, c = 27, d = 5, e = 0, f = 1, g = 6, h = (247 + 20 − 5 − 6 + 15) mod 30 = 1, i = 6, k = 3, l = (32 + 0 + 12 − 1 − 3) mod 7 = 5, m = 0. Then h + l − 7m + 114 = 120, so month = ⌊120/31⌋ = 3 (March) and day = (120 mod 31) + 1 = 28: Easter Sunday is 28 March 2027. The Orthodox rule gives d = 22, e = 6 and Julian 19 April, which is 2 May 2027 in the Gregorian calendar.
Easter dates 2025–2035
| Year | Western Easter | Orthodox Easter | Gap |
|---|---|---|---|
| 2025 | April 20 | April 20 | Same day |
| 2026 | April 5 | April 12 | 1 week |
| 2027 | March 28 | May 2 | 5 weeks |
| 2028 | April 16 | April 16 | Same day |
| 2029 | April 1 | April 8 | 1 week |
| 2030 | April 21 | April 28 | 1 week |
| 2031 | April 13 | April 13 | Same day |
| 2032 | March 28 | May 2 | 5 weeks |
| 2033 | April 17 | April 24 | 1 week |
| 2034 | April 9 | April 9 | Same day |
| 2035 | March 25 | April 29 | 5 weeks |
What each result means
- Western Easter Sunday = date([Year], floor(([h] + [l] – 7×[m] + 114)÷31), mod([h] + [l] – 7×[m] + 114, 31) + 1)
- Orthodox Easter is later by = [Orthodox Easter Sunday (Gregorian date)] – [Western Easter Sunday]
- Ash Wednesday = [Western Easter Sunday] – 46
- Palm Sunday = [Western Easter Sunday] – 7
- Good Friday = [Western Easter Sunday] – 2
- Easter Monday = [Western Easter Sunday] + 1
- Ascension Day = [Western Easter Sunday] + 39
- Pentecost (Whitsunday) = [Western Easter Sunday] + 49
- Corpus Christi = [Western Easter Sunday] + 60
- Orthodox Good Friday = [Orthodox Easter Sunday (Gregorian date)] – 2
- Golden number (year in the 19-year lunar cycle) = [a] + 1
- Days from today to Western Easter = [Western Easter Sunday] – today()
Formula
Western: a = y mod 19, b = ⌊y/100⌋, c = y mod 100, d = ⌊b/4⌋, e = b mod 4, f = ⌊(b+8)/25⌋, g = ⌊(b−f+1)/3⌋, h = (19a+b−d−g+15) mod 30, i = ⌊c/4⌋, k = c mod 4, l = (32+2e+2i−h−k) mod 7, m = ⌊(a+11h+22l)/451⌋, month = ⌊(h+l−7m+114)/31⌋, day = ((h+l−7m+114) mod 31) + 1 · Orthodox (Meeus): d = (19(y mod 19)+15) mod 30, e = (2(y mod 4)+4(y mod 7)−d+34) mod 7, Julian date = day ((d+e+114) mod 31)+1 of month ⌊(d+e+114)/31⌋, plus ⌊y/100⌋ − ⌊y/400⌋ − 2 days
Worked example
Inputs — Year: 2,027.
Results — Western Easter Sunday = Sun, March 28, 2027; Orthodox Easter Sunday (Gregorian date) = Sun, May 2, 2027; Orthodox Easter is later by = 35 days; Ash Wednesday = Wed, February 10, 2027; Palm Sunday = Sun, March 21, 2027; Good Friday = Fri, March 26, 2027; Easter Monday = Mon, March 29, 2027; Ascension Day = Thu, May 6, 2027; Pentecost (Whitsunday) = Sun, May 16, 2027; Corpus Christi = Thu, May 27, 2027; Orthodox Good Friday = Fri, April 30, 2027; Golden number (year in the 19-year lunar cycle) = 14; Days from today to Western Easter = 148 days.
Key terms
- Computus
- The calculation of the date of Easter from calendar and lunar tables.
- Paschal full moon
- The ecclesiastical full moon on or after 21 March; Easter is the following Sunday.
- Metonic cycle
- 19 years ≈ 235 lunar months, after which moon phases repeat on the same dates.
- Movable feast
- A church holiday whose date depends on Easter, such as Pentecost.
Frequently asked questions
When is Easter 2027?
Western Easter is on Sunday 28 March 2027 and Orthodox Easter on Sunday 2 May 2027 – five weeks apart.
What is the earliest and latest possible Easter?
Western Easter falls between 22 March and 25 April. The next 22 March Easter is in 2285; the last 25 April Easter was in 1943 and the next is in 2038.
Why do Western and Orthodox Easter differ?
The Orthodox churches compute Easter in the Julian calendar with the older lunar tables, which now run 13 days behind for the calendar and several days behind for the Moon.
When do both churches celebrate Easter together?
When both rules give the same Sunday – for example in 2025 (20 April), 2028 (16 April), 2031 (13 April) and 2034 (9 April).
Is Easter the Sunday after the first full moon of spring?
Approximately. The church uses a tabulated "ecclesiastical" full moon and fixes the equinox at 21 March, so in some years the date differs from the astronomical rule.
How is Ash Wednesday calculated?
46 days before Easter Sunday – 40 days of Lent plus the six Sundays, which are not counted as fast days.
What is the golden number?
The position of the year in the 19-year Metonic cycle (1 to 19); it determines the date of the ecclesiastical full moon.