Chinese metaphysics that
gets the chart right.
We built BeyondBazi because too many tools get the basics wrong. The Four Pillars is a precise system - when the pillars are wrong, everything that follows is wrong.
Why we built this
Bazi, or the Four Pillars of Destiny, is one of the most sophisticated systems in Chinese metaphysical tradition. It is also one of the most routinely miscalculated - by apps, by websites, and increasingly by AI chatbots that generate plausible-sounding but technically wrong outputs.
The most common errors are not subtle. Many tools use January 1 as the year boundary when the astrological year starts at Li Chun (around February 4). Many use approximate month boundaries instead of the actual solar terms. Some skip hidden stems entirely. These are not minor rounding issues - they change the pillars, which changes the entire reading.
BeyondBazi was built to do this correctly: documented sources, transparent conventions, consistent outputs. The same birth date and time always produces the same pillars, and we state openly how every element of the calculation works.
Our method
We use the Zi Ping (子平) method, the mainstream classical approach to Four Pillars analysis. Here is exactly how each pillar is calculated:
- Year pillar: The astrological year begins at Li Chun (立春, around February 4) when the sun reaches 315 degrees ecliptic longitude. Not January 1 and not the Lunar New Year. A person born between January 1 and Li Chun has their year pillar in the previous astrological year.
- Month pillar: Each solar month begins at one of the 12 Jie (節) solar terms. We use a lookup table of accurate dates covering 1920 to 2030, cross-referenced against astronomical computation. The month stem is derived using the Five Tigers rule (五虎遁), which links the year stem to the starting month stem.
- Day pillar: A continuous 60-day sexagenary cycle from a documented anchor: January 31, 1900 (Gregorian) is Jia Zi (甲子), cycle index 0. Every day pillar since then is counted from this anchor.
- Hour pillar: The 12 two-hour periods, with the hour stem derived from the day stem using the Five Rats rule (五鼠遁).
- Zi hour convention: The Zi hour (子時) spans 23:00 to 01:00 across midnight. We use Early Zi: 23:00-23:59 belongs to the current calendar day; 00:00-00:59 belongs to the next calendar day. This convention is clearly labelled in the calculator.
- True solar time: An optional correction for the longitude difference between your birth location and the UTC meridian. Note that the equation of time is not applied, which introduces a small error (up to 16 minutes). This is labelled as a known limitation.
Our principles
Documented sources
Every calculation rule is stated openly, including the anchor date, the solar term table, and the Five Tigers and Five Rats formulas.
Transparent limitations
Day Master strength uses a simplified heuristic. We say so on every reading. We do not claim the authority of a master's analysis.
Consistency
The same inputs always produce the same outputs. No randomness, no hidden adjustments, no "personalised" variance.
Cultural framing
Bazi is a tool for reflection drawn from a rich tradition. We frame readings as patterns to explore, not destiny to accept.
What BeyondBazi is not
BeyondBazi does not offer:
- A master's personalised consultation. Our readings are transparent, rule-based outputs.
- Predictions about specific events, relationships, health outcomes, or financial decisions.
- Medical, psychological, legal, or financial advice of any kind.
- A Chinese zodiac calculator. For Chinese zodiac, we recommend birthchartnumbers.com.
Bazi is a framework from Chinese cultural tradition with a long history of study and practice. We respect that tradition by applying it precisely and honestly.
About this site
BeyondBazi is an independent project. The calculator runs entirely in your browser - no birth data is sent to any server. Charts saved with "Save My Chart" are stored only in your browser's local storage.
We are based in Singapore and publish under the beyondbazi.com domain. For questions or feedback, visit our Contact page.
BeyondBazi is for cultural interest and self-reflection. Not fate, medical, or financial advice. The readings are rule-based outputs, not a master's analysis.