What this system examines
Zi Wei Dou Shu organizes a natal chart into twelve palaces to examine life areas, major stars, and changing periods as a connected system.
Free Zi Wei Dou Shu calculator online: twelve palaces
A free online Zi Wei Dou Shu calculator. Enter a birth date and two-hour birth period to see the twelve palaces, major stars and four transformations.
Build it here
Drawing the chart here stores nothing and sends nothing. Your birth details are sent only when you save the chart or ask a question, and without an account they are kept for seven days.
Drawing the chart is free and needs no account. Nothing is sent until you save the chart or ask a question.
How this system reads
How the result is formed
Calendar and birth inputs determine the palace layout and the star placements. The chart follows the birth details entered, down to the two-hour period.
How to read it responsibly
Small birth-time errors may alter palace placement. The chart is a cultural interpretive model and must not be presented as scientific proof or guaranteed fate.
After the Zi Wei Dou Shu calculator draws your chart, where to look first
Date and two-hour period
The calculator takes a Gregorian birth date and one of twelve two-hour periods, starting with Zi (子), from 23:00 to 01:00. The clock time is used as entered, with no correction for the birthplace, and the day turns at midnight, so a birth after 23:00 stays on the date you entered.
Find the life palace
The date is converted to the lunar calendar. Starting at the Yin (寅) palace for the first lunar month, the calculator counts forward to your birth month, then back one palace for each two-hour period from Zi (子) to yours: that is the Life palace (命宫). Counting forward instead gives the Body palace, and the other eleven palaces follow the Life palace in a fixed order: Siblings, Spouse, Children, Wealth and on to Parents.
Major stars and empty palaces
The stem and branch of the Life palace set the element bureau, shown as the phase bureau. From that bureau and the lunar day of birth, Zi Wei (紫微) is placed, and the other thirteen major stars follow from it. Some palaces receive no major star, and the chart leaves them empty. When the Wealth palace is empty, a reading borrows the major stars of the Fortune palace opposite.
The four transformations
The stem of the birth year turns four stars into Hua Lu (禄), Hua Quan (权), Hua Ke (科) and Hua Ji (忌). The table under the chart lists each star, its transformation and the palace it sits in. Here the year turns at the lunar new year, so a birth between the lunar new year and the Start of Spring can carry a different year stem from the BaZi chart.
Bring one question
Ask one question about the chart and a reading answers it in writing, naming the palaces and stars it reads from. A complete reading uses credits.
The other systems
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Zi Wei Dou Shu twelve palaces: how to read them
The Zi Wei Dou Shu twelve palaces are the labeled areas of a chart. Learn the twelve names, find your Life palace, and tell palaces from stars.
Common questions
- Is this Zi Wei Dou Shu calculator free, and in English?
- Free, no account needed. The page and its notes are in English; the chart writes the palaces and stars in Chinese characters, as the tradition does, and a written reading names them in English. Drawing it here keeps nothing, so a refresh clears the chart. A chart is kept once you save it or ask a question about it: seven days in this browser without an account, saved to your account after you sign in. An AI reading is written only when you ask for one: a short reading costs 10 credits and a complete reading 40. A new account's first short AI reading is free, and members' short readings use no credits.
- How does the calculator find the life palace?
- From the lunar month and the two-hour period of birth. Starting at the Yin (寅) palace for the first lunar month, it counts forward to the birth month, then back one palace for each period from Zi (子) to the birth period. The palace it lands on is the Life palace (命宫). Its stem and branch then set the element bureau, which with the lunar day of birth places Zi Wei (紫微).
- What if I do not know my two-hour birth period?
- The calculator needs one, because the Life palace is counted from the birth month and the period, and a different period moves it. If you are unsure between two periods, build the chart for each and compare where the Life palace and its major stars fall. The BaZi calculator on this site works without a birth time and gives three pillars.
- What are the twelve palaces and four transformations shown?
- The 12 palaces of Zi Wei Dou Shu (also written Ziwei Doushu) are Life, Siblings, Spouse, Children, Wealth, Health, Travel, Friends, Career, Property, Fortune and Parents, each on one earthly branch and each standing for one area of life. The four transformations are Hua Lu (禄), Hua Quan (权), Hua Ke (科) and Hua Ji (忌), given to four stars by the stem of the birth year. The table under the chart shows the star, the transformation and the palace.
- Why does the Zi Wei Dou Shu chart calculator ask for gender?
- The traditional calculation uses it to set the direction of the ten-year periods. It does not move the Life palace, the other palaces or the major stars.
- Can I enter a lunar date or a leap month in the Zi Wei Dou Shu calculator?
- No, you enter the Gregorian date and the Zi Wei Dou Shu calculator converts it to the lunar calendar itself, so there is no lunar or leap-month box. If you only know a lunar birthday, convert it first; the lunar option in the BaZi calculator shows the Gregorian date it used. A birth in a leap month counts as the month before for lunar days 1 to 15 and as the month after from day 16.
- Why can two Zi Wei Dou Shu calculators give different charts?
- Because the schools differ on a few rules and each calculator picks one. This one fixes three: the year turns at the lunar new year, not at Lichun; a birth in a leap month counts as the month before for lunar days 1 to 15 and as the month after from day 16; and the two-hour period from 23:00 to 01:00 is one Zi (子) period that stays on the date you entered, with no early and late Zi. Star placement and the four transformations follow one fixed set of rules, so if another chart differs, compare these three first.
- Does AI calculate the Zi Wei Dou Shu chart?
- No. A fixed calendar and star-placement engine builds the chart from the date, two-hour period and gender you enter, so the same details always give the same chart. AI is used only when you ask a question about the chart, and it then reads the chart that was already built.