Easter Date Calculator
Find Western Easter, Lent start, and Pentecost for any year.
What it does
Easter wanders the calendar by design. Western churches set it as the first Sunday after the paschal full moon on or after March 21, computed from tables fixed to the Gregorian calendar rather than from telescopes. The same rule that gave April 20 in 2025 gives April 5 in 2026 and March 28 in 2027.
The tool above runs the Gregorian computus for any year from 1583 to 9999. Enter the year to get Easter Sunday plus Ash Wednesday (46 days before) and Pentecost (49 days after), all in UTC date math. Defaults ask about 2026, so the page opens solved at Sun Apr 05 2026 with Wed Feb 18 2026 and Sun May 24 2026.
The algorithm looks fussy because history made it so: golden numbers track the 19 year moon cycle while century terms repair the Gregorian leap exceptions. Each remainder feeds the next until one code number splits into month and day. Practice years confirm the chain: 2025 lands Sun Apr 20 2025 with Lent from Wed Mar 05 2025 and Pentecost Sun Jun 08 2025.
Range checks keep expectations honest. Western Easter never leaves March 22 to April 25, and Eastern churches following the Julian paschalion often land one, four, or five weeks later. The page names Western dates only; Orthodox calendars need their own reckoning.
Use the table for coming years, then run your year. The math assumes the Gregorian reform already in force, so pre 1583 dates need the Julian computus instead. Within range it answers planning questions fast: which Sunday, when Lent opens, and when Pentecost closes the season.
How to use
- Enter a Gregorian year from 1583 to 9999.
- Read Easter Sunday first.
- Read Ash Wednesday for Lent start.
- Read Pentecost 49 days later.
- Check Eastern dates separately.
- Plan holidays around the Sunday.
Formula
- Y
- Gregorian year, 1583 to 9999.
- a to m
- Intermediate remainders of the algorithm.
- Easter
- Easter Sunday date.
Years run 1583 to 9999 in the Gregorian calendar only. Lent start subtracts 46 days and Pentecost adds 49 days in UTC date math. Results name Western Easter; Eastern Orthodox dates follow a different paschalion and may differ by weeks.
Worked example
Example: Easter 2026
Find Western Easter 2026 with the Gregorian computus, plus its Lent start and Pentecost.
- Golden inputs for 2026: a = 12, b = 20, remainders cascade.
- h = (228 + 24) mod 30 = 12; l = 30 mod 7 = 2.
- Month/day code = 12 + 2 + 114 = 128.
- Month = 128/31 = 4, day = (128 mod 31) + 1 = 5.
- Easter lands Sun Apr 05 2026.
- Lent opened Wed Feb 18 2026; Pentecost lands Sun May 24 2026.
Reference table
| Year | Easter | Lent opens | Pentecost |
|---|---|---|---|
| 2025 | Sun Apr 20 2025 | Wed Mar 05 2025 | Sun Jun 08 2025 |
| 2026 | Sun Apr 05 2026 | Wed Feb 18 2026 | Sun May 24 2026 |
| 2027 | Sun Mar 28 2027 | Wed Feb 10 2027 | Sun May 16 2027 |
| 2028 | Sun Apr 16 2028 | Wed Mar 01 2028 | Sun Jun 04 2028 |
| 2029 | Sun Apr 01 2029 | Wed Feb 14 2029 | Sun May 20 2029 |
Limits
- Western Easter only; Eastern differs.
- Gregorian calendar from 1583.
- Tables, not astronomical moon.
- No liturgical advice.
Common mistakes
- Using the true full moon instead.
- Counting Lent Sundays differently.
- Applying it before 1583.
- Mixing Julian and Gregorian dates.
- Expecting one fixed date.
Try it yourself
Quick checks. Answers sit tucked under each question.
Easter 2025?
Easter Sun Apr 20 2025. Lent Wed Mar 05 2025. Pentecost Sun Jun 08 2025.
Easter 2027?
Easter Sun Mar 28 2027. Lent Wed Feb 10 2027. Pentecost Sun May 16 2027.
Show the 2027 code number by hand.
a = 2027 mod 19 = 13. h = (247 + 24) mod 30 = 271 mod 30 = 1. l = 40 mod 7 = 5. Code = 1 + 5 + 114 = 120. Month 3, day 28.
Questions
How is Easter dated?
Western Easter: the first Sunday after the paschal full moon on or after March 21, computed with fixed tables (here the Gregorian anonymous algorithm) rather than the sky.
What is the possible range?
March 22 at earliest, April 25 at latest. Recent spans include 2027 on March 28 and 2025 on April 20.
When does Lent start?
46 days before Easter Sunday, counting Sundays in the Western reckoning used here. For 2026 that is Wed Feb 18 2026.
When is Pentecost?
49 days after Easter Sunday. For 2026 that is Sun May 24 2026.
Do Eastern churches differ?
Yes, where ranges differ: Eastern churches use the Julian paschalion, landing one, four, or five weeks later in many years.
Does it work before 1583?
No. Valid Gregorian input runs 1583 to 9999; earlier years need the Julian computus instead.