In the gregorian calendar the Easter date is at its earliest on March, 22nd and at its latest on April, 25th.
Because the formula of Gauss has exceptions and has limited validity, I used the Spencer Jones method as described in the book Astronomical Algorithms-second edition by Jean Meeus.
The Spencer Jones method is valid starting from 1583.
| divide | by | quotient | remainder |
| the year x | 19 | / | a |
| the year x | 100 | b | c |
| b | 4 | d | e |
| b + 8 | 25 | f | / |
| b - f + 1 | 3 | g | / |
| 19a + b - d - g + 15 | 30 | / | h |
| c | 4 | i | k |
| 32 + 2e + 2i - h - k | 7 | / | l |
| a + 11h + 22l | 451 | m | / |
| h + l - 7m + 114 | 31 | n | p |
Result n indicates the number of the month so n=3 means March and n=4 is April.
p+1 is the day on which it is Easter Sunday.
When applied for the year 2023
2023/19 --> a = 9
2023/100 --> b = 20, c = 23
20/4 --> d = 5, e= 0
(20+8)/25 --> f = 1
(20-1+1)/3 --> g = 6
(19*9+20-5-6+15)/30 --> h = 15
23/4 --> i = 5, k = 3
(32+2*0+2*5-15-3)/7 --> l = 3
(9+11*15+22*3)/451 --> m = 0
(15+3-7*0+114)/31 --> n = 4 (April), p = 8 (Easter Sunday = p+1 = 9)
Easter Sunday 2023 is on 9/4
Extreme data for Easter are 22/3 as in 1818 and 2285 and 25/4 as in 1886, 1943 en 2038.
The most frequent Easter date is April, 19th.
Follow this link to find the Easter dates for 1000 years from 1583 to 2582.