Calculation of Easter Sunday online for year 1980

ItemFormulaResult
Golden numbergn = (year % 19) + 15
Julian epactje = 11 × gn % 3025
Centuryce = year / 100 + 120
Solar correctionsc = 3 × (ce - 16) / 43
Lunar correctionlc = 8 × (ce - 15) / 251
Gregorian epactge = (je - 10 - sc + lc) % 3013
March date of Ecclesiastical full moon
(Click here for show conversion table)
for ge <= 23: fm = 44 - ge31
for ge = 24: fm = 49
for ge = 25 and gn < 12: fm = 49
for ge = 25 and gn >= 12: fm = 48
for ge >= 26: fm = 74 - ge
date of Ecclesiastical full moonMarch 31
Gregorian correctiongc = 10 + sc13
Day of week for Ecclesiastical full moon
The number 0 is Sunday, 1 is Monday, and so on until 6, which is Saturday
dfm = (year + year / 4 - gc + fm) % 71
March date of the first Sunday after the Ecclesiastical full moones = fm + (7 - dfm)37
Easter Sunday falls on the first Sunday after the Ecclesiastical full moonApril 6

Gregorian
epact
Ecclesiastical
full moon
23March 21
22March 22
21March 23
20March 24
19March 25
18March 26
17March 27
16March 28
15March 29
14March 30
13March 31
12April 1
11April 2
10April 3
9April 4
8April 5
7April 6
6April 7
5April 8
4April 9
3April 10
2April 11
1April 12
0April 13
29April 14
28April 15
27April 16
26April 17
25/25April 17/18
24April 18