Free BaZi Calculator — Four Pillars of Destiny
Four pillars of year, month, day and hour, with hidden stems, Five Element strength, Ten Gods, a useful-god suggestion and the luck pillars. The month pillar is derived from solar terms, not from the lunar first day. No sign-up required.
What BaZi is
Four Pillars of Destiny (Chinese: 八字, BaZi — literally “eight characters”) reads a life from the moment of birth. Each of the four pillars — year, month, day and hour — carries one Heavenly Stem and one Earthly Branch. Four pairs make eight characters, hence the name.
| Pillar | Stem | Branch | Usually read for |
|---|---|---|---|
| Year | Year stem | Year branch | Ancestry, origins, early childhood |
| Month | Month stem | Month branch | Parents, siblings, formative environment — this pillar decides elemental strength |
| Day | Day Master — the person themselves | Day branch | The self and marriage |
| Hour | Hour stem | Hour branch | Children, later life |
Unlike Zi Wei Dou Shu, which places stars into twelve palaces, BaZi uses no stars at all. Everything is read from the productive and controlling relations among the Five Elements, with the Day Master as the anchor.
Why the month pillar follows solar terms
This is where hand calculation goes wrong most often. The month pillar changes at a solar term, not on the first day of a lunar month — the Tiger month begins at Li Chun (start of spring), the Rabbit month at Jing Zhe, and so on.
Someone born within a few hours of a solar term boundary gets an entirely different month pillar, which then shifts the whole strength analysis and the useful god. The calculator derives solar-term moments from astronomical data, so there is no table to look up.
What the chart gives you
- The eight characters — four stems, four branches, plus the hidden stems inside each branch.
- Five Element strength — the weight of Metal, Wood, Water, Fire and Earth across the whole chart.
- Ten Gods — how each stem relates to the Day Master: Direct Officer, Seven Killings, Direct Resource, Indirect Resource, Friend, Rob Wealth, Eating God, Hurting Officer, Direct Wealth, Indirect Wealth.
- Useful god suggestion — the element to reinforce in order to balance the chart.
- Luck pillars — ten-year cycles, running forward or backward depending on the year stem and gender.
An honest note
The calculation itself — pillars, hidden stems, solar terms, luck cycles — follows classical rules and is deterministic. The interpretation is offered as a cultural reference in the East Asian tradition. It is not advice about your health, finances or legal affairs, and it does not replace your own judgement.