The BaZi Year Pillar: One Division, Plus the Start of Spring
The year pillar is the easiest of the four. Remember two things: subtract 4 and take the remainder, and the year only changes at the Start of Spring.
The formula
- Check that the birth came after that year's Start of Spring. If it came before, use the previous year.
- (Gregorian year − 4) divided by 10; the remainder gives the stem: 0 Jia (甲), 1 Yi (乙), 2 Bing (丙), 3 Ding (丁), 4 Wu (戊), 5 Ji (己), 6 Geng (庚), 7 Xin (辛), 8 Ren (壬), 9 Gui (癸).
- (Gregorian year − 4) divided by 12; the remainder gives the branch: 0 Zi (子), 1 Chou (丑), 2 Yin (寅), 3 Mao (卯), 4 Chen (辰), 5 Si (巳), 6 Wu (午), 7 Wei (未), 8 Shen (申), 9 You (酉), 10 Xu (戌), 11 Hai (亥).
Why subtract 4? Because the year 4 CE was a Jia-Zi year. Counting from there, the stems repeat every ten years and the branches every twelve, and the pair returns to Jia-Zi every sixty.
The Start of Spring in recent years
| Year | Start of Spring (UTC+8) | Year pillar from then | Year pillar before then |
|---|---|---|---|
| 2020 | Feb 4, 17:03 | Geng-Zi (庚子) | Ji-Hai (己亥) |
| 2021 | Feb 3, 22:58 | Xin-Chou (辛丑) | Geng-Zi (庚子) |
| 2022 | Feb 4, 04:50 | Ren-Yin (壬寅) | Xin-Chou (辛丑) |
| 2023 | Feb 4, 10:42 | Gui-Mao (癸卯) | Ren-Yin (壬寅) |
| 2024 | Feb 4, 16:27 | Jia-Chen (甲辰) | Gui-Mao (癸卯) |
| 2025 | Feb 3, 22:10 | Yi-Si (乙巳) | Jia-Chen (甲辰) |
| 2026 | Feb 4, 04:02 | Bing-Wu (丙午) | Yi-Si (乙巳) |
| 2027 | Feb 4, 09:46 | Ding-Wei (丁未) | Bing-Wu (丙午) |
| 2028 | Feb 4, 15:31 | Wu-Shen (戊申) | Ding-Wei (丁未) |
| 2029 | Feb 3, 21:20 | Ji-You (己酉) | Wu-Shen (戊申) |
| 2030 | Feb 4, 03:08 | Geng-Xu (庚戌) | Ji-You (己酉) |
| 2031 | Feb 4, 08:58 | Xin-Hai (辛亥) | Geng-Xu (庚戌) |
How we checked: we worked out dates from 1901 to 2099 by the formulas on this page (one day in every 29, all thirteen hours) and compared each chart with our chart engine: 32,565 charts, every one a match. The share of births before the Start of Spring is calculated year by year for 1960–2005.
The times are for UTC+8 (Taiwan, China, Hong Kong, Singapore); convert for other time zones. If you were born on the day of the Start of Spring, what matters is whether the birth came before or after the exact moment; see solar term boundaries.
The year pillar and your Chinese zodiac sign
The branch of the year pillar is your zodiac animal: Zi Rat, Chou Ox, Yin Tiger, Mao Rabbit, Chen Dragon, Si Snake, Wu Horse, Wei Goat, Shen Monkey, You Rooster, Xu Dog, Hai Pig. So in BaZi the zodiac sign also changes at the Start of Spring, not at Chinese New Year. The year pillar's na yin element is what people mean when they say what "fate element" someone was born with (Jia-Zi and Yi-Chou years, for example, are "Gold in the Sea"); see na yin elements.
Watch your chart being worked out, step by step
Enter your Gregorian birthday and hour. The tool follows the method on this page and shows how each of the year, month, day and hour pillars is calculated, then checks the result against our chart engine. Everything is calculated in your browser; nothing is uploaded.
Uses your Gregorian birthday, with the day changing at 11 p.m.; the solar terms are compared at the middle of your two-hour period (as in our main chart calculator).
A straight word: working it by hand is for understanding, not for replacing a calculator
Once you have worked a chart by hand, you know where every character in it comes from, and you can read other people's charts with more confidence. Real charts, though, turn on the exact moment of a solar term, daylight saving time and true solar time, and one slip costs you a whole pillar. When you are done, check it once with a calculator. Everything on this site is for reference and entertainment.
Work out your year pillar
Enter your birthday, and the tool shows that year's Start of Spring and works out your year pillar step by step.
Year pillar FAQ
How do you calculate the BaZi year pillar?
After the Start of Spring, (Gregorian year − 4) divided by 10 leaves the stem and divided by 12 leaves the branch; born before it, use the previous year.
I was born in January. Which year do I use?
Anyone born before the Start of Spring uses the previous year. The Start of Spring usually falls on February 3 to 5, so January births almost always take the previous year.
Does the zodiac sign change at Chinese New Year or the Start of Spring?
In BaZi both the year pillar and the zodiac sign change at the Start of Spring. Popular usage often switches at Chinese New Year, but BaZi charts always use the Start of Spring.