A birth year carrying a 辛 (Xīn) heavenly stem fixes the stems of all twelve months ahead of time. This is the bazi month stem table for xin year charts, produced by the Five Tigers rule (五虎遁 wǔhǔdùn): a 辛 year opens its first month on 庚 (Gēng), then each month advances one stem. The complete run follows.
The 12 month pillars for a Xin 辛 year
Months change at a major solar term (節 jié), not on a calendar date. Find your birth branch and read across to the pillar.
| Month | Branch | Starts at (solar term) | Month pillar |
|---|---|---|---|
| 1st | Tiger 寅 Yín | Li Chun 立春 (~4 Feb) | 庚寅 Gēng Yín |
| 2nd | Rabbit 卯 Mǎo | Jing Zhe 惊蛰 (~6 Mar) | 辛卯 Xīn Mǎo |
| 3rd | Dragon 辰 Chén | Qing Ming 清明 (~5 Apr) | 壬辰 Rén Chén |
| 4th | Snake 巳 Sì | Li Xia 立夏 (~5 May) | 癸巳 Guǐ Sì |
| 5th | Horse 午 Wǔ | Mang Zhong 芒种 (~6 Jun) | 甲午 Jiǎ Wǔ |
| 6th | Goat 未 Wèi | Xiao Shu 小暑 (~7 Jul) | 乙未 Yǐ Wèi |
| 7th | Monkey 申 Shēn | Li Qiu 立秋 (~7 Aug) | 丙申 Bǐng Shēn |
| 8th | Rooster 酉 Yǒu | Bai Lu 白露 (~7 Sep) | 丁酉 Dīng Yǒu |
| 9th | Dog 戌 Xū | Han Lu 寒露 (~8 Oct) | 戊戌 Wù Xū |
| 10th | Pig 亥 Hài | Li Dong 立冬 (~7 Nov) | 己亥 Jǐ Hài |
| 11th | Rat 子 Zǐ | Da Xue 大雪 (~7 Dec) | 庚子 Gēng Zǐ |
| 12th | Ox 丑 Chǒu | Xiao Han 小寒 (~5 Jan) | 辛丑 Xīn Chǒu |
A 辛 year opens on 庚 metal and reaches its own stem 辛 in the second month, the Rabbit. That early 辛卯, refined metal over spring wood, is the fingerprint of the Xīn column — the same layout a 丙 year uses.
A worked example
Take a birth in the Rabbit month (卯 Mǎo) of a 辛 year. The second row gives 辛卯 (Xīn Mǎo) — the year stem repeating on the month, metal directly over the wood it controls, a tense little pillar. The Rabbit month opens at Jing Zhe (惊蛰 jīngzhé) around 6 March, so a birth on 4 March of that year is still in the Tiger month and reads 庚寅 (Gēng Yín) instead. Two days apart on the calendar, a different stem and branch, which is why the solar term governs the row rather than the date. What the Rabbit’s single-minded Wood then does to each Day Master is set out on the Rabbit month page.
Which years carry the 辛 stem
Calendar years ending in 1 are 辛 years: 1991, 2001, 2011, 2021. The Li Chun rule applies without exception — the Ba Zi year opens at the solar term around 4 February, so January births in a calendar 辛 year still read from the previous 庚 column, and January births of the following calendar year usually still belong here. A birth in late January 2022, for example, sits in this table’s closing 辛丑 Ox month, inside the 辛 year that began at Li Chun 2021; the Ox month page works through exactly that stacked-boundary case.
What the month pillar governs
The month pillar carries the month palace, read first for career climate and for the parental line. Its deeper importance is structural: the month branch holds the season’s ruling element, and the season sets the baseline temperature of the whole chart. This is why the month branch weighs so heavily when we judge a strong or weak Day Master — a Day Master born into its own season starts already supported. In a 辛 year the month stems open on metal, pass through water and fire, and return to metal, shaping how the season’s support reaches the Day Master.
That seasonal gate has a precise grammar: the branches group into spring 寅卯辰, summer 巳午未, autumn 申酉戌 and winter 亥子丑, and each season hands every Day Master one of the five states (旺相休囚死 wàng xiàng xiū qiú sǐ), Prosperous down to Dormant. The signature 辛卯 month is a working illustration — a Xin Metal Day Master born there sits in spring at the Confined grade, metal labouring against the season’s Wood, a position read in full in Xin Metal born in spring.
Reading it in context
Treat the month stem as a first move, not a verdict; it interacts with the branch’s hidden stems and the rest of the chart. Under the Five Tigers rule, 辛 and 丙 (Bǐng) years share this column, so the month table for Bing 丙 years matches this one exactly. The master month stem table shows all five columns at once, and the stems and branches alphabet sets out the hidden stems each branch conceals.
Xin-year month stem FAQ
Why does the column open on 庚 rather than 辛?
Because the opening stem is computed, not copied. The rule reads: first-month (寅) stem index = (year-stem-index mod 5) × 2 + 2; each later month adds 1, mod 10. Year stems pair: 甲/己, 乙/庚, 丙/辛, 丁/壬, 戊/癸 share columns. With 甲 as 0, 辛 is 7; 7 mod 5 is 2, and (2 × 2) + 2 = 6 — the stem 庚. The year’s own 辛 then arrives naturally one step later, in the Rabbit month.
Is 辛丑 in this table the same as the 2021 year pillar?
Same two characters, different pillar. 2021 was a 辛丑 year, and separately every 辛 year contains a 辛丑 twelfth month. A chart can therefore carry 辛丑 in the year column, the month column, or both — they are read in their own palaces.
Does sharing a column with 丙 years mean anything for compatibility?
No. The shared column is pure calendar arithmetic from the Five Tigers formula. It has no bearing on how 辛 and 丙 people relate; that question runs through entirely different machinery.
Confirm your own Xin-year month pillar against the exact solar-term boundary — plot your full chart free with the Butcher Boy calculator and read it back against the table above.