BaZi calculator: your Four Pillars of Destiny and Day Master

What is BaZi (Four Pillars of Destiny)?

BaZi means "eight characters" in Chinese, and that is exactly what the chart is. Each of the four pillars (year, month, day, hour of birth) is written as two characters: a heavenly stem on top and an earthly branch underneath. Four pillars, two characters each, eight characters. From those eight characters a BaZi practitioner reads temperament, strengths, relationships, career aptitude and the timing of the decades ahead, using the logic of the five elements (Wood, Fire, Earth, Metal, Water) and the ways they feed and control each other.

If you know your Chinese zodiac animal, you already know one quarter of your BaZi chart: the animal is the earthly branch of your year pillar. What most people do not know is that the year pillar is the least personal of the four. The day pillar describes you and your closest relationships; the month pillar describes your working life and parents; the hour pillar describes your later years, children and inner life. The Chinese zodiac page and the Chinese zodiac compatibility calculator work from the year branch alone, which is why BaZi is the natural next step once the animals have got you curious.

The ten heavenly stems

The stems are the five elements each in a yang and a yin form, in a fixed order. Each has a traditional image that captures its character.

Jia (Yang Wood) is the tall tree: upright, principled, slow to bend. Yi (Yin Wood) is the vine or flower: flexible, adaptable, persistent. Bing (Yang Fire) is the sun: warm, generous, visible. Ding (Yin Fire) is the candle or lamp: focused, thoughtful, illuminating. Wu (Yang Earth) is the mountain: stable, dependable, immovable. Ji (Yin Earth) is the garden soil: nurturing, resourceful, quietly productive. Geng (Yang Metal) is raw ore or the axe: decisive, tough, just. Xin (Yin Metal) is refined metal or jewellery: precise, elegant, sensitive to being valued. Ren (Yang Water) is the ocean or river: expansive, intelligent, restless. Gui (Yin Water) is rain, mist or dew: intuitive, subtle, penetrating.

The twelve earthly branches

The branches are the twelve animals, each with a hidden element and a two-hour window of the day. Zi (Rat, Water, 11 p.m.–1 a.m.), Chou (Ox, Earth, 1–3 a.m.), Yin (Tiger, Wood, 3–5 a.m.), Mao (Rabbit, Wood, 5–7 a.m.), Chen (Dragon, Earth, 7–9 a.m.), Si (Snake, Fire, 9–11 a.m.), Wu (Horse, Fire, 11 a.m.–1 p.m.), Wei (Goat, Earth, 1–3 p.m.), Shen (Monkey, Metal, 3–5 p.m.), You (Rooster, Metal, 5–7 p.m.), Xu (Dog, Earth, 7–9 p.m.), Hai (Pig, Water, 9–11 p.m.). Each branch also contains one to three hidden stems, which is where much of a chart's subtlety lives. The full table is below.

Stems and branches combine in a sixty-pair cycle (the sexagenary cycle) that has been used to count years, months, days and hours in China for over three thousand years. Your four pillars are simply the four pairs that were current when you were born.

The Day Master: the element that is you

The single most important character in a BaZi chart is the heavenly stem of the day pillar, called the Day Master (Ri Zhu). It represents the self. Everything else in the chart is read in relation to it: the other elements are classified as the ones that produce you (Resource), the ones you produce (Output), the ones you control (Wealth), the ones that control you (Power or Officer) and the ones that are the same as you (Companions). These five relationships, each split by polarity, give the Ten Gods, the vocabulary a practitioner uses to describe your career, money, relationships and authority.

A Bing (Yang Fire) Day Master, for example, is produced by Wood (Resource: learning, support, mothers), produces Earth (Output: creativity, expression, children), controls Metal (Wealth: money, and in traditional readings the spouse for one partner), is controlled by Water (Power: career, discipline, and the spouse for the other), and is joined by other Fire (Companions: peers, siblings, competition). The same logic runs for every Day Master, which is why knowing yours is the starting point of any BaZi reading.

Strong, weak, and favourable elements

A practitioner then asks whether the Day Master is strong (supported by the season of the month branch and by Resource and Companion elements) or weak (outnumbered by the elements that drain or control it). A strong Day Master benefits from the elements that use its energy (Output, Wealth, Power); a weak one benefits from the elements that feed it (Resource, Companions). Those become your favourable elements, and they are the practical output of a BaZi chart: the colours, directions, industries, seasons and even people that tend to help you. It is also how BaZi timing works: each ten-year luck pillar and each annual pillar brings its own elements, and years that bring your favourable elements tend to be easier than years that bring the unfavourable ones.

2026: the Bing Wu year (Fire Horse)

The BaZi year that begins at Li Chun, around February 4, 2026, is Bing Wu: Yang Fire stem over the Horse branch, which is itself Fire. A double-Fire year. In element terms, 2026 feeds Earth Day Masters (Fire produces Earth), warms and supports Wood Day Masters who are then drained by it, pressures Metal Day Masters (Fire controls Metal), gives Water Day Masters something to work on (Water controls Fire) and adds heat to Fire Day Masters who may already have plenty. Note the date difference: the Chinese zodiac year of the Horse began at Lunar New Year on February 17, 2026, but BaZi uses the solar calendar, so for a BaZi chart the Horse year began on February 4. If your birthday falls between those two dates in any year, your zodiac animal and your BaZi year pillar can differ; the calculator uses the BaZi rule. The Year of the Horse page covers the animal itself.

What this calculator shows, and what the full chart adds

From a birth date alone, this tool computes two pillars exactly: the year pillar (stem and branch, so your animal and its element) and the day pillar (stem and branch, so your Day Master and the branch that represents your closest relationships, sometimes called the spouse palace). It also shows the element balance across those two pillars.

The month pillar needs the solar month, which depends on the date and the solar terms (twenty-four divisions of the year that start around the 4th–8th of each month), and the hour pillar needs the birth time and, strictly, the location and its longitude correction. With all four pillars, a practitioner can judge Day Master strength properly, identify favourable elements, read the Ten Gods in every position and calculate the luck pillars. That is the full BaZi chart, and it is the reading the AstraLink app is designed to add alongside the Western natal chart; early-access members get their full chart first. In the meantime, the birth chart calculator gives you the Western equivalent from date, time and place, and the Vedic astrology page explains the third major system people compare these with.

BaZi and relationships

In BaZi, compatibility is read mainly from the day pillars of two people: whether the day branches combine (the six harmonies), clash or harm, and whether each person's favourable elements are supplied by the other's chart. Two people whose year animals clash can have day branches that combine beautifully, which is one reason year-animal compatibility is treated as a first filter. The app's Chinese compatibility mode uses both layers; the compatibility hub explains the Western equivalent of the same idea.