Zi Wei Dou Shu Basics

Zi Wei Dou Shu (紫微斗数, "Purple Star Astrology") is a Chinese birth-chart system separate from BaZi. Instead of four pillars it uses twelve palaces arranged around the twelve earthly branches, and places more than a hundred stars in them according to the lunar birth date and hour. This article introduces the structure of a Zi Wei chart and the main concepts you need to read one.

Origins

Zi Wei Dou Shu is traditionally attributed to 陈抟 (Chen Tuan), a Daoist of the early Song dynasty, although the texts we have date from later centuries. It developed alongside BaZi and shares its building blocks — stems, branches, the five elements, yin and yang — but arranges them very differently. Where BaZi reads the balance of elements in eight characters, Zi Wei describes areas of life through the stars in each palace.

The chart layout

A Zi Wei chart is a square ring of twelve cells, one for each earthly branch, with 寅 traditionally at the bottom left. The centre is used for the birth data. Each cell is a palace, and each palace receives a name according to where the life palace falls:

The body palace (身宫) is a marker placed on one of these twelve, not a thirteenth palace. It is traditionally read as becoming more important in the second half of life.

Locating the life palace

The life palace is found from the lunar month and the birth hour: starting from 寅, count forward to the birth month, then count backward by the birth hour. Because the hour moves the life palace — and therefore the names of all twelve palaces — Zi Wei is far more sensitive to birth time than BaZi, where the hour only affects one pillar.

Each palace also receives a stem, derived from the year stem, so every palace is a stem-branch pair. The pair of the life palace determines the five-element bureau (五行局) — water 2, wood 3, metal 4, earth 5 or fire 6 — which is used to place the Zi Wei star and sets the starting age of the decade periods.

The fourteen major stars

The Zi Wei star (紫微) is placed from the lunar birth day and the bureau number. Five more stars follow it at fixed offsets — 天机, 太阳, 武曲, 天同, 廉贞 — forming the Zi Wei group. The Tian Fu star (天府) is placed opposite Zi Wei along a fixed axis, and seven stars follow it — 太阴, 贪狼, 巨门, 天相, 天梁, 七杀, 破军 — forming the Tian Fu group. Together they are the fourteen major stars (十四主星).

Auxiliary and minor stars — 文昌, 文曲, 左辅, 右弼, 天魁, 天钺, 擎羊, 陀罗, 火星, 铃星 and many others — are placed from the year, month or hour by their own rules.

Brightness

Each major star has a brightness grade depending on the palace branch: 庙 (temple, strongest), 旺, 得, 利, 平, 不 and 陷 (fallen, weakest). A bright star expresses its qualities more fully and constructively; a fallen star expresses them with more difficulty. Brightness tables vary somewhat between books, which is one reason rule sets need to be stated.

The Four Transformations

The year stem attaches four transformations (四化) to specific stars: 化禄 (prosperity), 化权 (authority), 化科 (reputation) and 化忌 (obstruction). For a 甲 year, for example, 廉贞 takes 化禄, 破军 化权, 武曲 化科 and 太阳 化忌. The palaces in which these transformed stars fall are read as places of emphasis, opportunity or friction. Some schools also apply transformations from palace stems ("flying" transformations), which is an advanced technique.

Decade periods

Like BaZi luck pillars, Zi Wei divides life into ten-year decade periods (大限). The first starts at the bureau number — age 2 for a water bureau, 6 for fire — in the life palace, then moves palace by palace forward or backward depending on year polarity and gender. Each decade is read as if its palace were the life palace for those ten years.

Reading a chart

A common first pass:

1. Read the major stars of the life palace and their brightness.
2. Read the life palace together with its "three directions and four squares" (三方四正): the wealth, career and travel palaces.
3. Note where the four transformations fall.
4. Find the current decade palace and read it the same way.

How the calculator works

The Zi Wei calculator converts the birth date to the lunar calendar, applies one stated rule set and shows the full board: palaces, major and minor stars, brightness, transformations and decade periods. It uses its own rules and does not borrow BaZi's 立春 year boundary — Zi Wei follows the lunar year. Clicking a palace shows its details.

BaZi or Zi Wei?

They answer different questions in different vocabularies. Using both on the same birth data is a good way to check birth-time accuracy and to see a life from two angles. See BaZi vs Zi Wei Dou Shu and what BaZi is.

Key points

• Zi Wei Dou Shu arranges fourteen major stars and many minor stars in twelve palaces, based on the lunar birth date and hour.
• The Life palace and the Body palace are located from the lunar month and hour. The five-element bureau then sets where the Zi Wei star falls.
• Palaces are read in groups. The Life palace is read with its opposite palace and two trine palaces (三方四正).
• Star brightness and the Four Transformations (化禄, 化权, 化科, 化忌) modify each star's expression.
• Empty palaces borrow stars from the opposite palace.
• Decade periods (大限) and annual charts add timing, much as luck pillars do in BaZi.
• A practical learning order: palaces and bureau, then major stars, then the Life group, then the Four Transformations, then timing.
• Zi Wei and BaZi share calendar foundations but use different symbols. Many practitioners use both side by side.

The calculator lays out the full chart, so you can follow each of these steps on your own birth data.

Key terms in this article

Hour Pillar · 时柱

The hour pillar covers one of twelve two-hour periods (时辰), starting with 子 at 23:00–01:00. Its stem is derived from the day stem by the "five rats" rule. Because the boundary is solar, true solar time can move a birth into the neighbouring hour.

True Solar Time · 真太阳时

True solar time is clock time corrected for longitude (four minutes per degree from the zone meridian) and the equation of time (up to about ±16 minutes over the year). It places the sun at its actual position, which is what traditional hours follow.

Sexagenary Cycle · 六十甲子

Pairing the ten stems with the twelve branches in order (yang with yang, yin with yin) gives sixty combinations, from 甲子 to 癸亥. The same cycle counts years, months, days and hours, which is why every pillar is one of these sixty pairs.

Four Pillars · 四柱

The Four Pillars are the year, month, day and hour of birth, each written as a heavenly stem over an earthly branch. Together they give eight characters, which is why the method is also called BaZi (八字, "eight characters"). The pillars are derived from the solar calendar of solar terms, not from the lunar month.

The twelve palaces in brief

Each palace covers one area of life. Starting from the Life palace and moving through the chart, they are: Life (命宫), Siblings (兄弟), Spouse (夫妻), Children (子女), Wealth (财帛), Health (疾厄), Travel (迁移), Friends (交友 or 仆役), Career (官禄), Property (田宅), Fortune or wellbeing (福德) and Parents (父母). The Body palace (身宫) is placed separately and shares a branch with one of these; it is traditionally read as the area that becomes more important in later life.

Palaces are read in groups. The Life palace is always read together with its opposite (Travel) and its two trine palaces (Wealth and Career). This group of four, called 三方四正, shows how the core personality connects to work, money and the outside world.

Major and minor stars

The fourteen major stars carry most of the interpretation, but a chart also contains many minor stars — the six auspicious stars such as 左辅 and 右弼, the six challenging stars such as 擎羊 and 陀罗, and many smaller ones. Beginners should learn the major stars and the Four Transformations first; minor stars refine a reading but rarely change its direction.

Empty palaces

A palace without a major star is called empty. It is not unlucky; it is read by borrowing the major stars from the opposite palace, usually with a note that the influence is less direct. Many charts have two or more empty palaces.

A learning order

1. Locate the Life and Body palaces and the five-element bureau.
2. Learn the fourteen major stars and their brightness.
3. Read the Life palace group (三方四正).
4. Add the natal Four Transformations.
5. Only then move to decade and annual charts.

The Zi Wei calculator lays out the full chart so you can follow these steps.

Frequently asked questions

Why is Zi Wei so sensitive to the birth hour? Because the hour fixes the life palace and therefore the meaning of every palace.

How are leap months handled? Schools differ; the calculator states the convention it uses.

What if the life palace has no major star? It is read by borrowing the major stars of the opposite palace (借对宫).

More answers in the Zi Wei FAQ.