How we calculate Zi Wei Dou Shu
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How our Zi Wei Dou Shu chart is built, step by step.
1. Birth time
We convert clock time to true solar time at your birthplace (daylight saving removed, longitude and equation of time applied), then to a lunar date and one of the twelve two-hour branches. 23:00–24:00 is the late Zi hour of the same day.
2. Chart rules
The year boundary is Lunar New Year, as is usual in Zi Wei (BaZi uses Lichun instead). The Life and Body Palaces come from lunar month and hour; the Five Element Bureau from the Life Palace stem and branch; the fourteen major stars from the lunar day and the Bureau; the four transformations from the year stem. Ten-year periods start from the Bureau number and run forward or backward by gender and year polarity.
3. How we check it
The chart is computed with an open-source Zi Wei library and checked palace by palace — stars, transformations and period ages — against fixed reference charts that run automatically before every release.
4. How we read it
We explain each star in plain words with what it tends to mean in that palace, and always show which stars and transformations a reading comes from. We don't make predictions about illness, death or lawsuits.
FAQ
Does Zi Wei use true solar time too?
Yes. The birth hour that places the Life Palace is taken from the same true solar time as our BaZi chart, so the two charts always agree on the hour.
How do you handle a leap lunar month?
The whole leap month is placed as the following lunar month, and the result page notes when this applies.
Which school do you follow?
The widely used Three-Harmony style: fourteen major stars, the four transformations by year stem, and ten-year periods by the Five Element Bureau.