# Does the date of Easter favor some dates over others? **URL:** \ **Category:** Factual Questions\ **Created:** [April 18, 2025, 3:48pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173 "2025-04-18T15:48:29Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Quimby](https://avatars.discourse-cdn.com/v4/letter/q/22d042/32.png) [@Quimby](https://boards.straightdope.com/u/Quimby)\ **Post date:** [April 18, 2025, 8:11pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/21 "2025-04-18T20:11:48Z")
Something that’s interesting (maybe?) is the date for Easter is weird because it was originally based on a date in the Jewish calendar (it was the first Sunday after 15 Nisan which is the first day of Passover) and the Jewish Calendar is lunar (this is why Jewish holidays shift around on the Gregorian Calendar year by year). It has changed some since then to distance it from Passover but this is why is doesn’t have a fixed date. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 18, 2025, 8:37pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/22 "2025-04-18T20:37:53Z")
More precisely, the Jewish calendar, like the Chinese calendar, is sol-lunar. That means that a year sometimes has 12 months and sometimes 13, so that on average, the year stays the same length as a solar year. This is in contrast to a purely lunar calendar, like the Muslim calendar, which always has a 12-lunar-month year, and which therefore slides out of synch with solar calendars over time. > [@DPRK](#): > > It is always going to be a simplified computation unless the church decides its calendar is going to be fixed to the actual astronomical phases of the moon and Earth’s orbit. The same may be said for the Jewish computus. Of course, some religions do base their official calendars on actual astronomical observations (though of course, these can be predicted extremely well, with modern astronomical knowledge). ---
**Author:** ![Pleonast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pleonast/32/1183_2.png) [@Pleonast](https://boards.straightdope.com/u/Pleonast)\ **Post date:** [April 18, 2025, 8:53pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/23 "2025-04-18T20:53:24Z")
> [@Quimby](#): > > It has changed some since then to distance it from Passover I don’t think that’s the reason it was changed. It was changed to standardize it across Christianity (_narrator: it failed_). The Last Supper is a part of Easter and a prototype of Communion, one of the two universal rites of Christianity. It is also widely considered by Christians to be a part of Passover and necessarily Jewish. ---
**Author:** ![Monty](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/monty/32/47_2.png) [@Monty](https://boards.straightdope.com/u/Monty)\ **Post date:** [April 18, 2025, 10:33pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/24 "2025-04-18T22:33:33Z")
Aren’t all the computations above for determing the date of Easter for Western Christianity? Eastern Christianity’s Easter is generally later, but this year the two branches of Christianity celebrate Easter at the same time. ---
**Author:** ![Baker](https://avatars.discourse-cdn.com/v4/letter/b/bb73d2/32.png) [@Baker](https://boards.straightdope.com/u/Baker)\ **Post date:** [April 18, 2025, 10:47pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/25 "2025-04-18T22:47:29Z")
The first Sunday after the first full moon following the spring equinox. Unless that day is a Sunday in which it’s a week later. Probably the earliest Easter in my lifetime was 2008. It was March 22. and lands then roughly every ninety years. Orthodox Easter is on different dates mostly because their ecclesiastical calendar is the old Julian calendar. ---
**Author:** ![burpo\_the\_wonder\_mutt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/burpo_the_wonder_mutt/32/365_2.png) [@burpo\_the\_wonder\_mutt](https://boards.straightdope.com/u/burpo_the_wonder_mutt)\ **Post date:** [April 18, 2025, 11:09pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/26 "2025-04-18T23:09:49Z")
> [@burpo\_the\_wonder\_mutt](#): > > it jumps to 2060 My spectacles are malfunctioning; the charts say 2066 is my next birthday/Easter confluence. Can I make those extra six years? How much Cadbury you got? ---
**Author:** ![JWT\_Kottekoe](https://avatars.discourse-cdn.com/v4/letter/j/3ec8ea/32.png) [@JWT\_Kottekoe](https://boards.straightdope.com/u/JWT_Kottekoe)\ **Post date:** [April 19, 2025, 12:11am UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/27 "2025-04-19T00:11:37Z")
> [@Jas09](#): > > No, I don’t think that’s right. It is defined based on the “paschal full moon”, which is based on the “ecclesiastical equinox” which is fixed at March 21. And this “paschal full moon” doesn’t have to actually be a full moon - it’s just a computation. Yes, that’s right. It is not the actual full moon. The Roman Catholic Church has an ecclesiastical algorithm to compute the date of the Paschal Full Moon. It looks a bit like the instructions on a tax form. Instead of writing out an equation, a set of steps is defined that involves things like a correction factor for each year and so forth. The advantage is that anyone can do the computation and no matter where they are, they will arrive at the same date. The date of the actual full moon depends on your time zone, so this algorithm removes that problem. ---
**Author:** ![RivkahChaya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rivkahchaya/32/8919_2.png) [@RivkahChaya](https://boards.straightdope.com/u/RivkahChaya)\ **Post date:** [April 19, 2025, 12:46am UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/28 "2025-04-19T00:46:04Z")
> [@FinsToTheLeft](#): > > My birthday ends up during Passover every few years. Flourless birthday cake is disappointing. My son was born on Oct. 10. When he was still a baby, I checked; he will turn 21 _on Yom Kippur._ That means champagne at the break-the-fast. If it were a day earlier, we’d be pouring him into his seat (and let’s be honest: probably his father too) at Kol Nidre, after a keg at the last meal before the fast started. My birthday is nowhere near my bat mitzvah portion, because it is January 7, and I turned 13 two years after the Blizzard of 78. People over 55 get it. My mother insisted on waiting until spring before spending thousands of (1980) dollars on a party only to have all our relatives’ flights canceled due to weather, and our local guests even afraid, or unable to venture out. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [April 19, 2025, 12:47am UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/29 "2025-04-19T00:47:36Z")
> [@Baker](#): > > The first Sunday after the first full moon following the spring equinox. Unless that day is a Sunday in which it’s a week later. As I learned it, the first Sunday after the first Monday after the first full moon after the vernal equinox. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 19, 2025, 12:58am UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/30 "2025-04-19T00:58:41Z")
That can’t be right, because then you’d never be able to get one before the very last days of March. Even if you get that Monday right away, you’d still need to wait nearly a week after the Equinox. ---
**Author:** ![Saint\_Cad](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/saint_cad/32/18907_2.png) [@Saint\_Cad](https://boards.straightdope.com/u/Saint_Cad)\ **Post date:** [April 19, 2025, 1:07am UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/31 "2025-04-19T01:07:59Z")
I think that might be the Orthodox calculation. I honestly don’t know if it is accurate. ---
**Author:** ![md-2000](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@md-2000](https://boards.straightdope.com/u/md-2000)\ **Post date:** [April 19, 2025, 6:25pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/32 "2025-04-19T18:25:32Z")
> [@Baker](#): > > Orthodox Easter is on different dates mostly because their ecclesiastical calendar is the old Julian calendar I see that Ukraine and the Ukrainian Orthodox Church has recently changed Christmas to occur on Dec. 25th instead of following the same (Julian) calendar as the Russian Orhtodox church. Not sure if this applies to Easter as well. ---
**Author:** ![zimaane](https://avatars.discourse-cdn.com/v4/letter/z/a3d4f5/32.png) [@zimaane](https://boards.straightdope.com/u/zimaane)\ **Post date:** [April 20, 2025, 3:37pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/33 "2025-04-20T15:37:50Z")
> [@Chronos](#): > > Of course, some religions do base their official calendars on actual astronomical observations (though of course, these can be predicted extremely well, with modern astronomical knowledge). Islamic authorities in each country have something like a “moon estimation committee” to determine the last day of Ramadan each year, and they don’t all set the same date, although the variation is small. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [April 20, 2025, 3:45pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/34 "2025-04-20T15:45:02Z")
Related question; this year, the Western and Eastern churches have Easter on the same date but not in other recent years. Any idea why they coincided? > 2024 date > March 31 (Western) > May 5 (Eastern) > 2025 date > April 20 (Western) > April 20 (Eastern) > 2026 date > April 5 (Western) > April 12 (Eastern) > 2027 date > March 28 (Western) > May 2 (Eastern) ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [April 20, 2025, 6:17pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/35 "2025-04-20T18:17:37Z")
I’m not sure there’s a satisfying answer to “why” they coincide. The Western and Eastern churches use different algorithms, both rather complicated, and sometimes they produce the same date. This graph shows the dates in both churches for 100 years starting in 1950. You can see that it’s not uncommon for them to be on the same date; it looks like it happens in about a quarter of the years. [![](https://upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Easter_date_graphs.svg/1280px-Easter_date_graphs.svg.png) ](https://upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Easter_date_graphs.svg/1280px-Easter_date_graphs.svg.png) ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 20, 2025, 10:31pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/36 "2025-04-20T22:31:40Z")
As I understand it, the algorithms are mostly the same, aside from some fine details, and the biggest difference is that they disagree on when “March 21” is. But if the first full moon after March 21 happens to be more than two weeks later, both churches will be using the same full moon, and so have the same Easter. ---
**Author:** ![Baker](https://avatars.discourse-cdn.com/v4/letter/b/bb73d2/32.png) [@Baker](https://boards.straightdope.com/u/Baker)\ **Post date:** [April 20, 2025, 10:55pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/37 "2025-04-20T22:55:44Z")
I saw an online article once talking about how the common dates will gradually be less common, because the calendars will keep on diverging. If I remember correctly sometime in the 2600’s they will be far enough apart that they won’t be able to be on the same date. ---
**Author:** ![JohnGalt](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johngalt/32/184_2.png) [@JohnGalt](https://boards.straightdope.com/u/JohnGalt)\ **Post date:** [April 21, 2025, 3:06am UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/38 "2025-04-21T03:06:18Z")
Saturday’s Washington Post has an interesting article about how and why Western and Orthodox Easters match this year and will match again in 2028. It doesn’t precisely describe the exact calculation, but has an interesting take: > [@](#): > > Several attempts have been made to fix a date for Easter over the years. In 1963, the Second Vatican Council of bishops said it “would not object if the feast of Easter were assigned to a particular Sunday of the Gregorian Calendar.” In 1997, the World Council of Churches (WCC) attempted to standardize the process I read this to mean that Easter would always be on the same day of the calendar, such as Christmas is always December 25th, but on a Sunday, just as Thanksgiving in the US is always on a Thursday. Perhaps the first Sunday in April? I doubt that they change will happen anytime soon. Here’s the WaPo gift article (hope it works): [https://wapo.st/4imiCoX](https://wapo.st/4imiCoX) ---
**Author:** ![DPRK](https://avatars.discourse-cdn.com/v4/letter/d/4491bb/32.png) [@DPRK](https://boards.straightdope.com/u/DPRK)\ **Post date:** [April 21, 2025, 8:05am UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/39 "2025-04-21T08:05:27Z")
If they want everybody to agree, is there some reason _not_ to have it on the first Sunday after the (actual) full moon on or after the (actual) equinox? ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [April 21, 2025, 9:45pm UTC](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173/40 "2025-04-21T21:45:31Z")
One difficulty with that is the astronomical spring Equinox and the astronomical full moon are both at specific points in time. Either might occur on March 22 in Europe and March 21 in the US due to time zone difference. If that also happens to be a Sunday or Saturday (depending on whether "after’ means “strictly after” or “on or after” there would be disagreement. I suppose you’d could define it as equinox or full moon in Rome (upsetting Protestants and Eastern Orthodox churches). Better would probably be Jerusalem time, I suppose. [Previous page](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173.md?page=1) [Next page](https://boards.straightdope.com/t/does-the-date-of-easter-favor-some-dates-over-others/1017173.md?page=3)