sexagenary Cycle

There appears to be no such table. (unsigned)

Fixed. -- GreenC 14:39, 24 July 2017 (UTC)

At least a Start class.

Want to help write or improve articles about Time? Join WikiProject Time or visit the Time Portal for a list of articles that need improving. -- Yamara 19:18, 17 January 2008 (UTC)

This article should be merged with Chinese astrology. ChongDae

It is fine existing as a separate article, as it is specific to it's title. Though the sexagesimal cycle is used in Chinese astrology, it is but one part. The Sexagesimal cycle is used for calendrical dates, but not necesarily always for Chinese astrology. I do not favour a merger. Dylanwhs 23:18, 7 May 2005 (UTC)

Someone should add columns allowing for the Vietnamese pronuncications of these terms. Prouddemocrat 17:32, 11 July 2005 (EST)

Are these specifically associated with lunisolar calendars? If so, shouldn't the article link to that, at least as a "see also? -- Jmabel | Talk 22:58, 10 November 2005 (UTC)

You have a good point. All traditional East Asian calendars that have used the sexagenary cycle have been lunisolar, and I don't think that the Gregorian calendar now used in East Asian countries has the sexagenary cycle applied to its years (it could, erroneously). The Tibetan calendar also uses the sexagenary cycle and is also lunisolar. My concern is with the use of at least the twelve animals in Turkey. Although I do not know that much about the old Turkish calendar, I don't think it was ever lunisolar. — Joe Kress 02:24, 11 November 2005 (UTC)

I've taken the liberty of adding it as a "see also". -- Jmabel | Talk 04:44, 16 November 2005 (UTC)

Since this page is on the Chinese sexagenary cylce, I'm wondering why all the in-text romanizations after the first section seem to be using Japanese pronunciation of the characters. Could someone who can read the Chinese add Chinese pronunciations or replace the Japanese ones? Obviously stuff like "Nihon Shoki" is fine since that's actually Japanese, but I think it would be good if the terminology were consistent about what language it's in. cmcswiggen

That info was transferred here due to merging the equivalent Japanese article with this article. The basic Chinese romanizations (ganzhi, tiangan, dizhi) are in the first paragraph, but better organization is needed. — Joe Kress 07:50, 11 January 2007 (UTC)

How do you pronounce "sexagenary?" —The preceding unsigned comment was added by 69.166.69.56 (talk • contribs) 22 August 2006.

I hope you don't mind if I don't trouble myself to work out the IPA, and I could be wrong here, but I pronounce it sex-uh-GEN-uh-ree. That's a U.S. pronunciation; I suspect a Brit might pretty nearly omit the fourth syllable. Does someone want to work out the IPA and add it to the article? - Jmabel | Talk 00:55, 24 August 2006 (UTC)

The overview is vague to the point of being misleading. It's only an overview for the Japanese system, not the system as a whole, but it never mentions that. Someone who didn't recognize the Japanese transliteration of the Hanzi would likely think that the whole calendar was adopted in the 7th century, which is wrong, wrong, wrong. Elijahmeeks 15:26, 28 February 2007 (UTC)

Yes, and the Japanese pronunciation of the terms dominate the body of the article. Highly awkward. --Do Not Talk About Feitclub (contributions) 03:19, 24 March 2007 (UTC)

I changed a verb so that the grammar was correct. anniid 07:28, 5 January 2008 (UTC)

Don't 甲子 and 庚子 have the same Japanese pronunciation? While they can use the kun readings won't it still get confusing? Ohwell32 21:40, 14 May 2007 (UTC)

The Chinese new year dates are wrong for many years Davidyan74 (talk) 08:33, 5 January 2009 (UTC)

Something is definitely wrong somewhere. I found 3 Wikipedia articles containing lists of new year dates:
• Chinese astrology
• Chinese calendar correspondence table
• Sexagenary cycle (this one)
Unfortunately, no two lists match exactly - and some deviations are quite large! The best bet would seem to be the Chinese astrology list, as it never disagrees with both other lists simultaneously. I wonder if an official list can be found somewhere on the Chinese internet? --Yawe (talk) 14:53, 18 May 2009 (UTC)

A user updated the new year's dates to begin at either the 4th or 5th of February each year. This way, the inclusion of the calculation of intercalary months is not calculated. The Chinese calendar is lunisolar, not solar. I shall probably revert the dates back to their original format in a while if I managed to prove myself correct. Mohamed 09:49, 15 January 2011 (UTC)

The Japanese cycle is called the "kanototori" cycle.98.242.74.75 (talk) 05:29, 13 July 2009 (UTC)

In the “Relation to the western calendar” section of Sexagenary cycle, the text reads “The actual year commence is based on Chinese Solar calendar, always February 4 of every year.” and a source is cited. However, in that very source, it is stated that the new year is usually on the 4th or 5th of February, and gives comprehensive tables year by year of the exact date and time at which the new year begins. These are mostly on the 4th, but some are on the 5th. This same exact problem (even down to citing the same source and not following what it says) occurs on Chinese zodiac, whereas Chinese astrology and Chinese New Year show the years based on the Chinese Lunar Calendar, with the date of the new year changing by several days or even weeks each year.Qaanol (talk) 00:25, 10 January 2011 (UTC)

Exactly. I did not notice your contribution at first but as you said the dates change each year, in the range of 11 days in particular. This way, the inclusion of the calculation of intercalary days is not present. The Chinese calendar is lunisolar, not solar. I shall probably revert the dates back to their original format in a while if I managed to prove myself correct. Mohamed 10:05, 15 January 2011 (UTC)

A more involved discussion is at Talk:Chinese astrology#Proposed changes to table, including a request for comment. — Joe Kress (talk) 08:43, 16 January 2011 (UTC)

I have rewritten the introductory paragraph, and the overview section, and have responded to two-year-old request for verifiable citations. I have covered the bare necessities of the Chinese situation up to the Han period. It would be good if someone would contribute the following additional sections: Sexagenary cycle in Japan, ... in Korea, ... in Tibet, in other places, perhaps also in contemporary folk traditions.

The mass of tables at the end of the article badly needs clearing up - I'll do it myself if their creators do not object. The table of "Ten Heavenly Stems" and "Twelve Earthly Branches" should go, as those topics have separate articles (with similar tables) of their own. The "Sexagenary Cycle" table should probably stay as is. The remarks following it need to be cleaned up or deleted, however. The endless tables correlating the sexagenary cycle with the international calendar should also go, to be replaced with two sentences describing the relationship. The "24 Cardinal Directions" image should go (or go somewhere else) since it is not connected with the sexagenary cycle.

All references to the on-line astrology web-page should go, as it is simply not a reliable source.

The final table for months and the accompanying comments make very little sense. Unless a better source can be found for it, it should go.--TheNothingNihilates (talk) 03:05, 10 June 2011 (UTC)

The article says:

When 2008 is divided by 60 the remainder is 28.

Actually for 2008/60 I get 33.46666 -- perhaps what was meant is 60/2008, in which case I get .02988 -- can someone please clarify? I'd like to try and figure out some signs from the 19th century but can't figure out how to do it, the article is unclear. Green Cardamom (talk) 00:50, 12 December 2011 (UTC)

2008 equals 60 × 33 + 28; and 28 is the remainder. What the article says is correct. See remainder --Kusunose 04:16, 12 December 2011 (UTC)

I see. Well, figured it out, but still not very easy for non-math people. I'm going to write a step-by-step. Green Cardamom (talk) 06:48, 12 December 2011 (UTC)

Green, about your last edit on Dec. 12, you are right that "1964 / 60 = 32 + remainder" is misleading--it sounds too much like 1964/60 = 32 +44 = 76! (32 remainder 44 is short for 32+ 44/60)
However, it is wrong to say just 1964 / 60 = 32, because it isn't. The remainder is part of the division answer unless you qualify "division." You have to say "1964 / 60 = 32 with remainder 44", or " 1964 / 60 rounded down to the integer is 32", or "1964 / 60 is 32 by integral division", etc.
Actually, when you do the division on paper, you automatically get the remainder (44) as well as the (integral) quotient (32), so you don't need the extra step 1964- (60 * 32) = 44.

How about
1964 / 60 = 44 with remainder of 44 ("dividing by 60 and taking the remainder")
(to find the remainder use "1964 - (60*32) = 44")
44 = Fire Goat…. Stone-turner (talk) 01:47, 13 December 2011 (UTC)

I disagree. What you wrote above is complicated and confusing. "1964 / 60 = 44 with remainder of 44" only makes sense if your an experience math person capable of parsing the language. The example as currently written in the article is written for non-math people, straight-forward and easy for anyone to understand and follow, it doesn't assume familiarity with the concept of "remainder". Honestly, when I see the word "remainder" I think of a very different concept than the mathematical one. Your obviously a math person but most people are not. It took me 30 minutes last night to piece together all the clues to figure out how to do it, I've never in my life run into the math concept of "remainder" (or I have long since forgotten how), I can assure you that is true for most people. And reading the remainder article was not easy either. Just keep the example simple for anyone to follow and don't force them to do difficult math (though I realize it's not difficult for you or once one becomes familiar with it). Green Cardamom (talk) 02:23, 13 December 2011 (UTC)

I added a note about discarding any fraction. I still can't follow your explanation when you wrote above:
1964 / 60 = 44 with remainder of 44 ("dividing by 60 and taking the remainder") (to find the remainder use "1964 - (60*32) = 44")
Alright so I divide 1964/60 and I get 32.73333 .. where did the 44 come from? Then it says to find the remainder "1964 - (60*32) = 44" .. but I can't find the remainder 44 unless I first know the 32 number, which means it's two-step process, as is currently done in the article's example. 1. First find the 32 number using division, then 2. calculate out to find the 44 number using the remainder formula. Green Cardamom (talk) 02:38, 13 December 2011 (UTC)

Can't you at least come up with something better than "1964 / 60 = 32" or "248 / 60 = 4", because that is very confusing.Stone-turner (talk) 02:41, 13 December 2011 (UTC)

I just added the note to drop any fraction. Most people will understand what's being said here, it's a simple division statement. Green Cardamom (talk) 03:41, 13 December 2011 (UTC)

The formula section is unsourced, and the formula's don't work, mathematically, that I can tell, per above. I've added an expert tag, an unsourced tag, and restored the tables back to 1804. If there are working formula's please do update that section so we can easily figure out using the formula method, but you'll need to do a better job explaining how they work and with clear examples that actually work as described. Until then please don't delete the tables.Green Cardamom (talk) 01:05, 12 December 2011 (UTC)

I've done some rewriting on the part of calculation. There are indeed working formulas for both BC and AD years; now it is just up to providing it with more good sources. NoNews! 05:00, 12 December 2011 (UTC)

I deleted this sentence from the history. "According to Chinese historical records, the calendar was invented by the Yellow Emperor in the year 2637 BC, the 61st year of his reign" It cited Aslaksen's paper as basis. But what Aslaksen actually writes is "Some claim that the calendar was invented by the Yellow Emperor,Huángdì (黄帝)), in 2637 BCE in the 61st year of his reign….Modern scholars consider the Yellow Emperor to be a mythological figure. So this whole discussion of ancient dates [what is year 1] is just a curiosity." But in any case, it is not relevant to the history of the cycle since the cycle was not used for dating years until the Han Dynasty. It was at first related to the location in the zodiac of the planet Jupiter during the year (Smith's paper), and so it is clear that the dates of the Yellow Emperor's rule were based on the year cycle, not visa-versa.

But when illustrating repetition, in lieu of a better date, I used his reign (not the start of the calendar) and added an explanation. Stone-turner (talk) 02:19, 27 December 2011 (UTC)

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The sexagenary calendar cycle isn't just "a cycle of sixty terms used for reckoning time in China and the East Asian cultural sphere." It's also used in the traditional Tamil calendar and possibly other traditional South Asian calendars that are similar. Can someone please verify exactly which traditional South Asian calendars use this cycle and update the first sentence? Otherwise the beginning feels like it's only favouring the East Asian traditions and insulting other traditions. — Jclu: talk-contribs 10:02, 23 November 2017 (UTC)

In the section "Overview" the first sentence ends with "the twelve Earthly Branches representing the years of Jupiter's duodecennial orbital cycle". From a historical point of view, this must be a much later "representation", as the Sexagenary cycle was first used for the recording of days (as a kind of "week" of 60 days, running without any kind of interruption through both lunar months and seasonal years) in the late Shang era about 1250 B.C.E. Only about 1000 years later (in the Qin and early Han eras, as earliest about 250 B.C.E.) do we find any evidence for use of the Sexagenary cycle for recording of years. As Jupiter's sidereal orbital cycle is (a bit less than) 12 years, it seems, at least to me, to be probable that the Chinese at this time correlated "the twelve Earthly Branches" with Jupiter's "residing" in different parts of the Chinese "zodiac" (possibly from contact with astronomers from India, whose "Indian 60-year cycle", however, really follows Jupiter's "true" orbital period and therefore often only has 59 years), but this cannot be the original source for the cycle of "the twelve Earthly Branches", which existed more than 1000 years earlier. Does anyone have any information about the "true", historical source of this Chinese cycle of "the twelve Earthly Branches"? And if so, could that information (of course from a scientific, cited source) be incorporated into this Wikipedia page? /Erik Ljungstrand (Sweden) — Preceding unsigned comment added by 130.241.158.201 (talk) 07:30, 28 March 2018 (UTC)

It would be very useful if this page also included some more text about the very ancient counting of days by means of the Sexagenary cycle. After all, this "60-day-week" is, as far as we know, the oldest use of the Sexagenary cycle, possibly more than 1000 years older than the counting of years which the page tells us a lot about. Above all, the page should give its readers some "fixed point" for calculating this Sexagenary counting of days, as e.g. the information that yesterday, Monday 2 April 2018 C.E., i.e. 17th day of the 2nd Chinese month, year "wù-xū" ("戊戌"), was the first day of this Sexagenary day-count, i.e. a "jiǎ-zǐ" ("甲子") day - which, to the best of my knowledge, is true. /Erik Ljungstrand (Sweden) — Preceding unsigned comment added by 130.241.158.201 (talk) 13:35, 3 April 2018 (UTC)

Hey Q5968661, thank you so much for taking the time to plot out the days on a chart!

However, I'm finding it extremely hard to follow. I want to write a longer explanation for using it, like the one that exists for cyclic years to Western years, but I'm afraid I don't understand what you want people to do for the century column(s). You want people to mod the century by 2, which I take to mean that the only answer is either row 01 or 00--yet the century sub-column on the right contains much higher numbers. I'd be able to follow along if there were an example century given that didn't fall under either N10 or N3. Would you be so kind as to either explain it to people unfamiliar with this type of math, or perhaps edit in a new example? --A garbage person (talk) 19:57, 27 April 2018 (UTC)

Thanks for your interest in it and sorry for my poor English! The century mod 2 or 4 is for the Julian calendar and the higher numbers on the right are for Gregorian calender (from October 15, 1582). I will write an algorithm for mental calculation of sexagenary day cycle as a whole and hope you will like it. Q5968661 (talk) —Preceding undated comment added 02:55, 28 April 2018 (UTC)

Heavenly stems		N	Earthly branches
Century			Century
Julian calendar	Gregorian calendr		Julian calendar	Gregorian calendr
		01
	17 24	02	02 06 10 14	18
01 03 05 07 09 11 13 15	22	03		21
		04		24
	20	05	01 05 09 13
	18	06		17
	23	07		20 23
00 02 04 06 08 10 12 14	16	08	00 04 08 12
	21	09
	19	10		16 19
		11	03 07 11 15	22
		12

• ... -3 -1 01 03 05 07 09 11 13 15 are odd numbers (mod 2 = 1) and ... -4 -2 00 02 04 06 08 10 12 14 are even numbers (mod 2 = 0).
• ... -7 -3 01 05 09 13 (mod 4 = 1), ... -6 -2 02 06 10 14 (mod 4 = 2), ... -5 -1 03 07 11 15 (mod 4 = 3), ... -8 -4 00 04 08 12 (mod 4 = 0).

Is that clear? -- Q5968661 (talk)

Magnificent! Thank you for the explanation. I really appreciate it. And I'm so glad you took this on--I tried to figure out the math on my own and I failed miserably. -- A garbage person (talk) 17:38, 30 April 2018 (UTC)

I'm glad you really appreciate it. Would you like to help me write a explanation for using the look-up table? Thank you in advance. -- Q5968661 (talk) 14:44, 1 May 2018 (UTC)

It took me longer than I thought, but I've added an explanation to the table. I've also made some accessibility edits to make it easier for disabled people to use—things like using something other than color to mark something as important, more explanatory table headers, adding tooltips within the table for explanation, etc. Take a look and see if I've done it justice. --A garbage person (talk) 21:45, 9 May 2018 (UTC)
Thank you very much! It's very kind of you. -- Q5968661 (talk) 08:40, 10 May 2018 (UTC)

Q5968661 (talk) 00:13, 2 May 2018 (UTC)

Though smaller, this chart is confusing. If I wanted to find the stem-branch of July 23, 2018, would it automatically be C, since that's the column that 23 is in? Would it be B, where the row for July and column for 23 meet? Would it be J, where the column for 23 and the row for century 20 meet? Would it be I, where column 23 and year 18 meet? Also, it's difficult for people using screen-readers to understand tables with multiple headers. I'm even a little confused with the headers in this table!
Again, I appreciate your work, it's just hard for me to understand and parse. — Preceding unsigned comment added by A garbage person (talk • contribs) 22:09, 9 May 2018 (UTC)
Sorry for that. The date letter for July 23 is B, where the row for July and column for 23 meet. C in the row for century 20 and B in the row for year 18 are in the same column. So the stem for the day is C which stands for 03 or 丙 (bing). B (July 3,13 and 23) → B (year 18) → C (century 20), that is all the B days in the year are C day (丙日). And all the J days are A day (甲日, JJA) in this year,... -- Q5968661 (talk) 15:20, 10 May 2018 (UTC)

Look-up table for sexagenary days

Heavenly stem								A 甲	B 乙	C 丙	D 丁	E 戊	F 己	G 庚	H 辛	I 壬	J 癸	天 干										干 支 纪 日 速 查 表
Century				Date				01	02	03	04	05	06	07	08	09	10	Year of the century
								11	12	13	14	15	16	17	18	9	20
								21	22	23	24	25	26	27	28	29	30
								31
16				Aug	Julian			A	B	C	D	E	F	G	H	I	J	00	02	21	23	40	42	61	63	80	82
		23		Feb	Jun	Jul		J	A	B	C	D	E	F	G	H	I	04	06	25	27	44	46	65	67	84	86
18				Jan	Apr	May	Feb	I	J	A	B	C	D	E	F	G	H	08	10	29	31	48	50	69	71	88	90
	20				Mar		Jan	H	I	J	A	B	C	D	E	F	G	12	14	33	35	52	54	73	75	92	94
								G	H	I	J	A	B	C	D	E	F	16	18	37	39	56	58	77	79	96	98
		22						F	G	H	I	J	A	B	C	D	E	01	03	20	22	41	43	60	62	81	83
17			24					E	F	G	H	I	J	A	B	C	D	05	07	24	26	45	47	64	66	85	87
								D	E	F	G	H	I	J	A	B	C	09	11	28	30	49	51	68	70	89	91
	19			Nov	Dec			C	D	E	F	G	H	I	J	A	B	13	15	32	34	53	55	72	74	93	95
		21		Sep	Oct			B	C	D	E	F	G	H	I	J	A	17	19	36	38	57	59	76	78	97	99
Earthly branch								A 子	B 丑	C 寅	D 卯	E 辰	F 巳	G 午	H 未	I 申	J 酉	K 戌	L 亥	地 支
Century				Date				01	02	03	04	05	06	07	08	09	10	11	12	Year of the century
								13	14	15	16	17	18	9	20	21	22	23	24
								25	26	27	28	29	30	31
				Julian			Nov	A	B	C	D	E	F	G	H	I	J	K	L	00	07	16	23	32	39	48	55	64	71	80	87	96
		20	23			Sep		L	A	B	C	D	E	F	G	H	I	J	K		14		30		46		62		78		94
17								K	L	A	B	C	D	E	F	G	H	I	J	05		21		37		53		69		85
						Jul		J	K	L	A	B	C	D	E	F	G	H	I	03	12	19	28	35	44	51	60	67	76	83	92	99
			24	Jan	May			I	J	K	L	A	B	C	D	E	F	G	H		10		26		42		58		74		90
		21		Jan	Mar			H	I	J	K	L	A	B	C	D	E	F	G	01		17		33		49		65		81		97
	18						Dec	G	H	I	J	K	L	A	B	C	D	E	F	08	15	24	31	40	47	56	63	72	79	88	95
							Oct	F	G	H	I	J	K	L	A	B	C	D	E	06		22		38		54		70		86
						Aug		E	F	G	H	I	J	K	L	A	B	C	D		13		29		45		61		77		93
		22		Feb	Jun			D	E	F	G	H	I	J	K	L	A	B	C	04	11	20	27	36	43	52	59	68	75	84	91
16	19			Feb	Apr			C	D	E	F	G	H	I	J	K	L	A	B	02		18		34		50		66		82		98
								B	C	D	E	F	G	H	I	J	K	L	A		09		25		41		57		73		89

For 11 May 2018: S = I→I→J = 癸, B = G→G→D = 卯, S-B = JD = 癸卯 (40). Q5968661 (talk) 15:24, 11 May 2018 (UTC)
For the Julian date, treat the year as a whole and mod it by 80, and use the first row (as its century row) to look up the stem-branch. For May 11, 2063 BC: -2062 mod 80 = 18, S = (II) C, B = (GG) E, SB = CE (丙辰, 53). Q5968661 (talk) 04:04, 12 May 2018 (UTC)

Algorithm for mental calculation

Expressions:

• a = year mod 80
• b = (5a + [a/4]) mod 60
• c = 10 + [century/4] - century (mod 60 if necessary) for the Gregorian date, c = 8 for the Julian date
• d = day of the month
• e = (day of the year ) mod 60 (according to the month, see the table below)
• f = (b + c + d + e) mod 60
• S = f mod 10
• B = f mod 12

Examples:

1. December 26, 1893

a = 1893 mod 80 ＝ 53
b = (53 mod 12 × 5 + [53/4]) mod 60 ＝ 38
c = 10 + [18/4] - 18 = -4
d = 26
e = 34
f = (38 - 4 + 26 + 34) mod 60 = 34
S = 34 mod 10 = 4
B = 34 mod 12 = 10

2. April 2, 2018

a = 2018 mod 80 = 18
b = (18 mod 12 × 5 + [18/4]) mod 60 = 34
c = 10 + [20/4] - 20 = -5
d = 2
e = 30
f = (34 - 5 + 2 +30) mod 60 = 1
S = B = 1

3. December 25, 105 BC (-104)

a = -104 mod 80 = 56
b = (56 mod 12 × 5 + [56/4]) mod 60 = 54
c = 8
d = 25
e = 34
f = (54 + 8 + 25 + 34) mod 60 = 1
S = B = 1

4. January 1, 1600 (leap year)

a = 1600 mod 80 ＝ 0
b = 0
c = 10 + [16/4] - 16 = -2
d = 1
e = -1
f = (0 - 2 + 1 - 1) mod 60 = 58
S = 58 mod 10 = 8
B = 58 mod 12 = 10

5. January 1, 1900 (common year)

a = 1900 mod 80 ＝ 60
b = (60 mod 12 × 5 + [60/4]) mod 60 = 15
c = 10 + [19/4] - 19 = -5
d = 1
e = 0
f = (15 - 5 + 1 + 0) mod 60 = 11
S = 11 mod 10 = 1
B = 11 mod 12 = 11

Q5968661 (talk) 12:26, 14 May 2018 (UTC)

Since the ToC is auto-generated I don't see how this could have happened, but the ToC lists a subsection called Algorithm for mental calculation, and nothing happens when you click it. I can't find that text in the page either. Equinox ◑ 12:19, 13 October 2019 (UTC)

That section was added and immediately hidden without removing the bracketed "===" that made its title a heading. I removed "===". The section is still there, and still hidden (click on [show]), but without a section title. — Joe Kress (talk) 17:33, 13 October 2019 (UTC)

Adding on to the discussion above, the current look-up table for the sexagenary days is quite confusing and I could not find any explanation on how to use it. Considering that it looks different from its counterpart on the Chinese page, I think that we should check its correctness. I am especially critical of the fact that both days and months are on the same side of the table, both are referring to columns, so you cannot find any intersection of them, as is done in the Chinese version.

If I have understood the Chinese table correctly, in order to find the stem-branch for a given date, e.g. 25 January 2020, one first needs to check whether or not one needs to use the red numbers. Since both century (20, left side) and year (20, left side) are marked in red, we do need to use the red numbers. Then check the intersection of day (25, top) and month (red 01, left side), and arrive at 乙. Then look for the rows marked by the century (20, left side) and the year (20, right side). In the row for the year (20, right side) search for 乙. In this column, move up (or down, accordingly) until you reach the row marked by the century (20, left side). In the intersection you will find 丁, so the stem for 25 January 2020 is 丁.

For the branch, do the same in the bottom half of the table, that is: Find the intersection of day (25) and month (red 01), arrive at 未. In the row marked by the year (20, right side), find the cell with 未, then move up in that column until you reach the row marked by the century (20, left side) and in the intersection find 卯, so the branch is 卯 and therefore the stem-branch for 25 January 2020 is 丁卯, which can easily be verified through Sinocal.

However, I could not figure out how to use the tables provided on the English page. If we do not provide any information on how to use it, I think we should remove it from the article.

Ph. Immel (talk) 14:48, 6 February 2020 (UTC)

The formula for years AD is (year – 3) mod 60 and for years BC is (year + 2) mod 60.

How can that be accurate? Is the BC year number considered to be negative? That could be made more explicit. —Tamfang (talk) 06:36, 1 March 2024 (UTC)