The Easy (?) Way: The fourteen calendars necessary for a perpetual calendar. | Which of the fourteen calendars goes with which year | Back to Boring Stuff
PERPETUAL CALENDAR
translated and adapted from that appearing in the Calendario Atlante De Agostini, 1985
This "perpetual calendar" permits one to determine the day of the week corresponding to any date from the beginning of the common era to December 31, 2399. Establishing the date (for example, January 17, 1963), first of all find, in the column of the pertinent century (1900), the letter in the horizontal line with the last two digits of the year (63); in our case the letter is F. Then find in the table of months in what column the letter F appears in a horizontal line with the desired month (January): in our case, the sixth column. Finally in the corresponding vertical column (that is, the sixth) of the table of days, find the day of the week that appears in the horizontal line with the desired date (17): it turns out that January 17, 1963, is a Thursday.
For leap years there are two letters corresponding to the year. Use the first letter for January and February, and the second for the other months.
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CENTURY (Julian Calendar) from A.D. 1 to October 4, 1582
0 100 200 300 400 500 600
700 800 900 1000 1100 1200 1300
1400 1500
DOMINICAL LETTER YEAR (last two digits of the desired year)
DC ED FE GF AG BA CB 00
B C D E F G A 01 29 57 85
A B C D E F G 02 30 58 86
G A B C D E F 03 31 59 87
FE GF AG BA CB DC ED 04 32 60 88
D E F G A B C 05 33 61 89
C D E F G A B 06 34 62 90
B C D E F G A 07 35 63 91
AG BA CB DC ED FE GF 08 36 64 92
F G A B C D E 09 37 65 93
E F G A B C D 10 38 66 94
D E F G A B C 11 39 67 95
CB DC ED FE GF AG BA 12 40 68 96
A B C D E F G 13 41 69 97
G A B C D E F 14 42 70 98
F G A B C D E 15 43 71 99
ED FE GF AG BA CB DC 16 44 72
C D E F G A B 17 45 73
B C D E F G A 18 46 74
A B C D E F G 19 47 75
GF AG BA CB DC ED FE 20 48 76
E F G A B C D 21 49 77
D E F G A B C 22 50 78
C D E F G A B 23 51 79
BA CB DC ED FE GF AG 24 52 80
G A B C D E F 25 53 81
F G A B C D E 26 54 82
E F G A B C D 27 55 83
DC ED FE GF AG BA CB 28 56 84
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CENTURY (Gregorian Calendar) from October 15, 1582 to December 31, 2399
1500 1600 1700 1800 1900
2000 2100 2200 2300
DOMINICAL LETTER YEAR (last two digits of the desired year)
-- BA C E G 00
F G B D F 01 29 57 85
E F A C E 02 30 58 86
D E G B D 03 31 59 87
CB DC FE AG CB 04 32 60 88
A B D F A 05 33 61 89
G A C E G 06 34 62 90
F G B D F 07 35 63 91
ED FE AG CB ED 08 36 64 92
C D F A C 09 37 65 93
B C E G B 10 38 66 94
A B D F A 11 39 67 95
GF AG CB ED GF 12 40 68 96
E F A C E 13 41 69 97
D E G B D 14 42 70 98
C D F A C 15 43 71 99
-- CB ED GF BA 16 44 72
-- A C E G 17 45 73
-- G B D F 18 46 74
-- F A C E 19 47 75
-- ED GF BA DC 20 48 76
-- C E G B 21 49 77
-- B D F A 22 50 78
-- A C E G 23 51 79
-- GF BA DC FE 24 52 80
-- E G B D 25 53 81
C D F A C 26 54 82
B C E G B 27 55 83
AG BA DC FE AG 28 56 84
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MONTH DOMINICAL LETTER
January, October A B C D E F G
February, March, November D E F G A B C
April, July G A B C D E F
May B C D E F G A
June E F G A B C D
August C D E F G A B
September, December F G A B C D E
DATE DAY OF THE WEEK
1 8 15 22 29 Su Sa Fr Th We Tu Mo
2 9 16 23 30 Mo Su Sa Fr Th We Tu
3 10 17 24 31 Tu Mo Su Sa Fr Th We
4 11 18 25 We Tu Mo Su Sa Fr Th
5 12 19 26 Th We Tu Mo Su Sa Fr
6 13 20 27 Fr Th We Tu Mo Su Sa
7 14 21 28 Sa Fr Th We Tu Mo Su
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