The lunation year has 354 days in a common year and either 383 in a short leap year or 384 days in a long leap year. It’s divided into 12 months of systematic, alternating length: 30 and 29 days with certain exceptions.
Weeks are not used with the IMC. The date notation specified in IC is commonly used for the ILC, but is not a mandatory part of it.
The lunar year contains either 12 or 13 complete lunar months.
A lunar month or lunation has 29 or 30 days. Although it can be astronomically defined exactly from new moon to new moon, e.g. at a reference point like 0° 0°,
with a day belonging to the lunation the majority of its hours belong to,
the 12 common months of the International Lunar Calendar alternate between 30 and 29 days.
Only the 13th, leap month or leap lunation, conveniently positioned at the end of the year, can differ in length: It has 29 or, slightly more often, 30 days in order to synchronize with astronomic reality.
A lunar month belongs to the month year the majority of its days (15 to 29 or 30) fall into.
A leap lunation of 30 days may never start on 17 December because it would have 15 days in the new year, i.e. that lunar month either has 29 days only or it is the first lunation of the following year.
International lunar month lengths compared to cognates
ILC
Hebrew
Buddhist
Label
Days
Short
Long
Early short
Early long
Common
Leap
L01
30
29
29
29
29
30
30
L02
29
30
30
29
29
29
29
L03
30
30
29
30
30
30
30
L04
29
29
30
30
29
29
29
L05
30
30
29
29
30
30
30
L06
29
29
30
30
29
29/30
29/30
L07
30
30
29
29
30
30
30
L08
29
29
30
30
29
29
30
L09
30
30
29
29
30
30
29
L10
29
29/30
30
30
29
29
30
L11
30
30/29
29/30
29/30
30
30
29
L12
29
29
30/29
30/29
29/30
29
30
L13
30/29
—
29
—
30/29
—
29
Σ
354; 383–384
353–355
382–384
353–355
382–384
354–355
384–385
Month numbering[]
International lunar months ordinal numbering equivalents in common 12-month years
ILC
Hebrew
Chinese
Buddhist
Biblical
Civil
Modern
Earthly
Civil
Traditional
L01
11
05
12
02
10
02
03
04
L02
12
06
01
03
11
03
04
05
L03
01
07
02
04
12
04
05
06
L04
02
08
03
05
01
05
06
07
L05
03
09
04
06
02
06
07
08
L06
04
10
05
07
03
07
08
09
L07
05
11
06
08
04
08
09
10
L08
06
12
07
09
05
09
10
11
L09
07
01
08
10
06
10
11
12
L10
08
02
09
11
07
11
12
01
L11
09
03
10
12
08
12
01
02
L12
10
04
11
01
09
01
02
03
Offset
−2
+4
−1
+1
−3
+1
+2
+3
International lunar months ordinal numbering equivalents in leap 13-month years
ILC
Hebrew
Chinese
Buddhist
Biblical
Civil
Modern
Earthly
Civil
Traditional
L01
11
05
12
02
10
02
03
04
L02
12
06
01
03
11
03
04
05
L03
01
07
02
04
12
04
05
06
L04
02
08
03
05
01
05
06
07
L05
03
09
04
06
02
06
07
08
L06
04
10
05
07
03
07
08
09
L07
05
11
06
08
04
08
09
10
L08
06
12
07
09
05
09
10
11
L09
07
01
08
10
06
10
11
12
L10
08
02
09
11
07
11
12
13
L11
09
03
10
12
08
12
13
01
L12
10
04
11
13
09
13
01
02
L13
11
05
12
01
10
01
02
03
International lunar months ordinal numbering equivalents after leap 13-month years
ILC
Hebrew
Chinese
Buddhist
Biblical
Civil
Modern
Earthly
Civil
Traditional
L01
12
06
13
02
11
02
03
04
L02
13
07
01
03
12
03
04
05
L03
01
08
02
04
13
04
05
06
L04
02
09
03
05
01
05
06
07
L05
03
10
04
06
02
06
07
08
L06
04
11
05
07
03
07
08
09
L07
05
12
06
08
04
08
09
10
L08
06
13
07
09
05
09
10
11
L09
07
01
08
10
06
10
11
12
L10
08
02
09
11
07
11
12
01
L11
09
03
10
12
08
12
01
02
L12
10
04
11
01
09
01
02
03
Month names[]
West Asian and European traditions[]
The various Muslim or Islamic Hijri calendars in current use always have 12 months per year, although previous local calendars did have intercalation (Nasi’). In the Tabular Islamic calendar, there are alternating 30:29 days in a month, and the final, twelfth month has 30 days in a leap year which happens 11 times in each 30-year leap cycle (by one of several established patterns). Their mapping to L01 through L12 or L13 therefore differs every year from the previous one.
The Jewish or Hebrew year is more closely related to the concept of the ILC except that both its month numbering variants are different, as is the point of astronomic reference (i.e. Jerusalem).
Ecclesiastical Jewish counting begins with Nisan (L03–L05), while civil Israeli counting starts with Tishrei (L09–L11).
The month lengths are fixed except that one day may be shifted from Kislev to Cheshvan to comply with certain holiday restrictions.
The traditional Chinese lunisolar calendar also has the full moon in the middle of each month. Its year usually starts with the second new moon after the Northern winter solstice. Each month can be repeated as a leap month and has either 29 or 30 days.
The traditional division of a month into three week-like periods, called 旬 (xún, jun, sun), of 10ish days each is not supported.
The Chinese solar terms or – incorrectly – “fortnights”, i.e. half-Zodiacs lasting a 15° portion of the ecliptic, which is 15 or 16 days, are not supported (yet) either.
International lunar months with Chinese 月 yuè equivalents in common years
The Buddhist calendar variants also have lunar months.
While modern counting starts with the month equivalent to L04 (after the Northern vernal equinox) in common years, most traditions start the month count with L12, but some also with L11 or L10.
There is no dedicated leap month, instead the month equivalent to L07 is repeated traditionally and always has 30 days.
The preceding month, equivalent to L06, may be lengthened from 29 to 30 days.
International lunar months with Buddhist equivalents
Common
Leap
Pali
Sanskrit
Burmese
Khmer
Lao
Sinhala
Thai
L01
L01
Phussa
Pausha, Pauṣa
ပြာသို
បុស្ស
ປຸສສ
දුරුතු
ปุสส
L02
L02
Māgha
Māgha
တပို့တွဲ
មាឃ
ມາດ
නවම්
มาฆ
L03
L03
Phagguṇa
Phālguna
တပေါင်း
ផល្គុន
ຜັກຄຸນ
මැදින්
ผัคคุณ
L04
L04
Citta
Chaitra, Caitra
တန်ခူး
ចេត្រ
ຈິຕ
බක්
จิตร
L05
L05
Vesākha
Vaisakha, Vaiśākha
ကဆုန်
ពិសាខ
ວິສາຂະ
වෙසක්
วิสาข
L06
L06
Jeṭṭha
Jyeshta, Jyaiṣṭha
နယုန်
ជេស្ឋ
ເຊດ
පොසොන්
เชษฐ
L07
L07 L08
Āsāḷha
Aashaadha, Āṣāḍha
ဝါဆို
អាសាឍ
ອາສາລະຫະ
ඇසළ
อาสาฬห
L08
L09
Sāvaṇa
Shraavana, Śrāvaṇa
ဝါခေါင်
ស្រាពណ៍
ສາວະນະ
නිකිණි
สาวน
L09
L10
Poṭṭhapāda
Bhaadra, Bhādrapada / Proṣṭhapāda
တော်သလင်း
ភទ្របទ
ພັດທະຣະບົດ
බිනර
ภัทรบท
L10
L11
Assayuja
Ashvin, Āśvina
သီတင်းကျွတ်
អស្សុជ
ອັດສະວະຍຸດ
වප්
อัศวยุช
L11
L12
Kattika
Kārtika
တန်ဆောင်မုန်း
កត្តិក
ກັດຕິກາ
ඉල්
กัตติกา
L12
L13
Māgasira
Agrahayana / Mārgaśirṣa
နတ်တော်
មិគសិរ
ມິຄະສິນ
උඳුවප්
มิคสิร
Types of years[]
Brief overview of year types
Type
First date
Last date
Days
Lunations
Possible following year types
S01
Dec17
Jan03
383
13
C08, C07*
S02
Dec18
Jan04
383
13
C09, C08*
S03
Dec19
Jan05
383
13
C10, C09*
S04
Dec20
Jan06
383
13
C11, C10*
S05
Dec21
Jan07
383
13
C12, C11*
S06
Dec22
Jan08
383
13
C13, C12*
S07
Dec23
Jan09
383
13
C14, C13*
S08
Dec24
Jan10
383
13
C15, C14*
S09
Dec25
Jan11
383
13
C16, C15*
S10
Dec26
Jan12
383
13
C17, C16*
S11
Dec27
Jan13
383
13
C18, C17*
S12
Dec28
Jan14
383
13
C19, C18*
L01
Dec17
Jan04
384
13
C09, C08*
L02
Dec18
Jan05
384
13
C10, C09*
L03
Dec19
Jan06
384
13
C11, C10*
L04
Dec20
Jan07
384
13
C12, C11*
L05
Dec21
Jan08
384
13
C13, C12*
L06
Dec22
Jan09
384
13
C14, C13*
L07
Dec23
Jan10
384
13
C15, C14*
L08
Dec24
Jan11
384
13
C16, C15*
L09
Dec25
Jan12
384
13
C17, C16*
L10
Dec26
Jan13
384
13
C18, C17*
L11
Dec27
Jan14
384
13
C19, C18*
C01
Dec28
Dec16
354
12
S01, S01*, L01, L01*
C02
Dec29
Dec17
354
12
S02, S02*, L02, L02*
C03
Dec30
Dec18
354
12
S03, S03*, L03, L03*
C04
Dec31
Dec19
354
12
S04, S04*, L04, L04*
C05
Jan01
Dec20
354
12
S05, S05*, L05, L05*
C06
Jan02
Dec21
354
12
S06, S06*, L06, L06*
C07
Jan03
Dec22
354
12
S07, S07*, L07, L07*
C08
Jan04
Dec23
354
12
S08, S08*, L08, L08*
C09
Jan05
Dec24
354
12
S09, S09*, L09, L09*
C10
Jan06
Dec25
354
12
S10, S10*, L10, L10*
C11
Jan07
Dec26
354
12
S11, S11*, L11, L11*
C12
Jan08
Dec27
354
12
S12, S12*, L12*, C01
C13
Jan09
Dec28
354
12
C02, C01*
C14
Jan10
Dec29
354
12
C03, C02*
C15
Jan11
Dec30
354
12
C04, C03*
C16
Jan12
Dec31
354
12
C05, C04*
C17
Jan13
Jan01
354
12
C06, C05*
C18
Jan14
Jan02
354
12
C07, C06*
C19
Jan15
Jan03
354
12
C08, C07*
S01*
Dec17
Jan02
383
13
C07
S02*
Dec18
Jan03
383
13
C08
S03*
Dec19
Jan04
383
13
C09
S04*
Dec20
Jan05
383
13
C10
S05*
Dec21
Jan06
383
13
C11
S06*
Dec22
Jan07
383
13
C12
S07*
Dec23
Jan08
383
13
C13
S08*
Dec24
Jan09
383
13
C14
S09*
Dec25
Jan10
383
13
C15
S10*
Dec26
Jan11
383
13
C16
S11*
Dec27
Jan12
383
13
C17
S12*
Dec28
Jan13
383
13
C18
L01*
Dec17
Jan03
384
13
C08
L02*
Dec18
Jan04
384
13
C09
L03*
Dec19
Jan05
384
13
C10
L04*
Dec20
Jan06
384
13
C11
L05*
Dec21
Jan07
384
13
C12
L06*
Dec22
Jan08
384
13
C13
L07*
Dec23
Jan09
384
13
C14
L08*
Dec24
Jan10
384
13
C15
L09*
Dec25
Jan11
384
13
C16
L10*
Dec26
Jan12
384
13
C17
L11*
Dec27
Jan13
384
13
C18
L12*
Dec28
Jan14
384
13
C19
C01*
Dec29
Dec16
354
12
S01, L01
C02*
Dec30
Dec17
354
12
S02, L02
C03*
Dec31
Dec18
354
12
S03, L03
C04*
Jan01
Dec19
354
12
S04, L04
C05*
Jan02
Dec20
354
12
S05, L05
C06*
Jan03
Dec21
354
12
S06, L06
C07*
Jan04
Dec22
354
12
S07, L07
C08*
Jan05
Dec23
354
12
S08, L08
C09*
Jan06
Dec24
354
12
S09, L09
C10*
Jan07
Dec25
354
12
S10, L10
C11*
Jan08
Dec26
354
12
S11, L11
C12*
Jan09
Dec27
354
12
S12, L12, C01
C13*
Jan10
Dec28
354
12
C02
C14*
Jan11
Dec29
354
12
C03
C15*
Jan12
Dec30
354
12
C04
C16*
Jan13
Dec31
354
12
C05
C17*
Jan14
Jan01
354
12
C06
C18*
Jan15
Jan02
354
12
C07
Dates of lunations in common years
Type
Prev. Dec.
January
February
March
April
May
June
July
August
September
October
November
December
Next Jan.
Type
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
S01
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
L01
S01
L01
L13
L01
L01
S02
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S02
L02
L13
L01
L02
S03
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S03
L03
L13
L01
L03
S04
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S04
L04
L13
L01
L04
S05
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S05
L05
L13
L01
L05
S06
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S06
L06
L13
L01
L06
S07
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S07
L07
L13
L01
L07
S08
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S08
L08
L13
L01
L08
S09
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S09
L09
L13
L01
L09
S10
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S10
L10
L13
L10
S11
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S11
L11
L13
L11
S12
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S12
C01
L01
C01
C02
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C02
C03
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C03
C04
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C04
C05
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C05
C06
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C06
C07
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C07
C08
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C08
C09
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C09
C09'
L13
C09'
C10
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C10
C11
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C11
C12
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C12
C13
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C13
C14
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C14
C15
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C15
C16
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C16
C17
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C17
C18
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C18
C19
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C19
Dates of lunations in leap years
Type
Prev. Dec.
January
February
March
April
May
June
July
August
September
October
November
December
Next Jan.
Type
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
S01*
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
L01
S01*
L01*
L13
L01
L01*
S02*
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S02*
L02*
L13
L01
L02*
S03*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S03*
L03*
L13
L01
L03*
S04*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S04*
L04*
L13
L01
L04*
S05*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S05*
L05*
L13
L01
L05*
S06*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S06*
L06*
L13
L01
L06*
S07*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S07*
L07*
L13
L01
L07*
S08*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S08*
L08*
L13
L01
L08*
S09*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S09*
L09*
L13
L01
L09*
S10*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S10*
L10*
L13
L01
L10*
S11*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S11*
L11*
L13
L11*
S12*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L13
S12*
L12*
L13
L12*
C01*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C01*
C02*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C02*
C03*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C03*
C04*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C04*
C05*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C05*
C06*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C06*
C07*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C07*
C08*
L12
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C08*
C08*'
L13
C08*'
C09*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C09*
C10*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C10*
C11*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C11*
C12*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C12*
C13*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C13*
C14*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C14*
C15*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C15*
C16*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C16*
C17*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C17*
C18*
L13
L01
L02
L03
L04
L05
L06
L07
L08
L09
L10
L11
L12
L01
C18*
Weeks[]
30:29 blocks by weeks, Monday start
Bim 1
Bim 2
Bim 3
Bim 4
Bim 5
Bim 6
L01
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L03
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L05
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L07
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L09
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L11
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L02
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L04
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L06
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L08
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L10
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L12
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30:29 blocks by weeks, Tuesday start
Bim 1
Bim 2
Bim 3
Bim 4
Bim 5
Bim 6
L01
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L03
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L05
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L07
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L09
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L11
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L02
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L04
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L06
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L08
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L10
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L12
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30:29 blocks by weeks, Wednesday start
Bim 1
Bim 2
Bim 3
Bim 4
Bim 5
Bim 6
L01
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L03
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L05
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L07
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L09
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L11
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L02
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L04
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L06
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L08
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L10
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L12
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30:29 blocks by weeks, Thursday start
Bim 1
Bim 2
Bim 3
Bim 4
Bim 5
Bim 6
L01
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L03
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L05
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L07
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L09
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L11
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L02
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L04
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L06
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L08
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L10
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L12
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30:29 blocks by weeks, Friday start
Bim 1
Bim 2
Bim 3
Bim 4
Bim 5
Bim 6
L01
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L03
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L05
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L07
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L09
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L11
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L02
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L04
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L06
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L08
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L10
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L12
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30:29 blocks by weeks, Saturday start
Bim 1
Bim 2
Bim 3
Bim 4
Bim 5
Bim 6
L01
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L03
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L05
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L07
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L09
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L11
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L02
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L04
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L06
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L08
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L10
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L12
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30:29 blocks by weeks, Sunday start
Bim 1
Bim 2
Bim 3
Bim 4
Bim 5
Bim 6
L01
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L03
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L05
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L07
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L09
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L11
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
L02
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L04
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L06
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L08
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L10
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
L12
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
Effects on Computus[]
Dates of lunations relevant for the date of Easter
Type
Prev. Dec.
January
February
March
April
May
June
July
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
01
02
03
04
05
06
07
08
09
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
S01*, L01*
L01
L02
L03
L04
L05
L06
L07
L08
S01, L01
L03
L04
L05
L06
L07
L08
S12*, L12*
L12
L01
L02
L03
L04
L05
L06
L07
L08
S12, C01
L03
L04
L05
L06
L07
L08
C12
L13
L01
L02
L03
L04
L05
L06
L07
C12*
L13
L01
L02
C18*
L13
L01
L02
L03
L04
L05
L06
L07
C19
L02
L03
L04
L05
L06
L07
In the earliest lunation year, L01 ends on 15 January. There are nominal new moons on 16 January, 14 February and 16 (or 15 after leap day) March. The next nominal full moon (15th day of L04) is on 30 (29) March. Easter is the Sunday in 31 (30) March through 6 (5) April.
In the latest lunation year, L01 starts on 15 January. There are nominal new moons on 14 February and 15 (14) March. The next nominal full moon (15th day of L03) is on 29 (28) March. Easter is the Sunday in 30 (29) March through 5 (4) April.
Easter therefore is in L03 in all years that start after 8 (9) January and in L04 in all other years because of the date of the first nominal full moon after 21 March.
Alternatively, Easter could be redefined to always occur on the Sunday in L04-16…22, for instance. That is as late as 4 (3) May in the Gregorian calendar after nominal full moon on 28 (27) April.