BaZi Calculator
Enter your birth date, time and place to get the complete Four Pillars. The time is corrected to true solar time using your birthplace longitude and the timezone actually in force that year.
What BaZi is
BaZi — literally "eight characters", also called Four Pillars — expresses your birth year, month, day and hour as four pairs of a Heavenly Stem and an Earthly Branch. Eight characters in total. It uses no stars; the reading comes from the balance and interaction of the Five Elements.
| Pillar | Governs | Boundary set by |
|---|---|---|
| Year | Ancestry, early life, background | Start of Spring — not 1 January |
| Month | Parents, career, young adulthood | Solar terms — not lunar months |
| Day | Yourself and your spouse (the day stem is you) | Rolls at the 子 hour |
| Hour | Children, later life, inner life | True solar time, two hours wide |
Why the time needs correcting
The hour pillar is a quarter of the chart, and a 时辰 is two hours wide. Clock time is not solar time: it needs correcting for your birthplace longitude, and for the timezone actually in force in your birth year. Almost every tool skips the second part.
Peninsular Malaysia and Singapore only adopted UTC+8 on 1 January 1982. Before that it was UTC+7:30, and UTC+9 under Japanese occupation. The full explanation, and how to check.
Common questions
What if I don't know my birth time?
The year, month and day pillars are still exact — only the hour pillar and anything depending on it becomes unreliable. Casting with 12:00 noon works, as long as you treat the hour pillar as an estimate.
Solar or lunar date?
Use the solar (Gregorian) date — the one on your IC or passport. BaZi month pillars are set by solar terms, so they never depended on lunar months anyway.
How is BaZi different from Zi Wei Dou Shu?
BaZi reads timing and balance through the Five Elements; Zi Wei Dou Shu describes character and structure through twelve palaces and their stars. Both derive from the same birth moment, so they are not independent confirmations of each other. Zi Wei calculator.