Zi Wei main star

What is Zi Wei Dou Shu?

Zi Wei Dou Shu (紫微斗數, sometimes rendered Purple Star Astrology) is a Chinese astrological system built around a grid of twelve palaces. Your birth date and hour fix where the grid starts; from there, fourteen major stars and a large cast of minor ones are placed into the palaces by rule. It is a different system from BaZi — same culture, same calendar, entirely different machinery — and the two are often read side by side rather than in competition.

The twelve palaces come first

Unlike Western astrology, the houses are not fixed to the horizon — the whole grid rotates depending on your birth month and hour. The first palace to be located is the Life palace (命宮), and every other palace is counted from it in a fixed order. This is why the birth hour matters so much here: shift the hour and the entire grid rotates, so the same stars land in completely different areas of life.

Then the stars are placed by rule, not by observation

The fourteen major stars are not planets and have no astronomical positions. They are placed by calculation from the lunar date, the hour, and the chart's Five Element Class (五行局). This is worth being clear about: nothing in a Zi Wei chart is looked up in an ephemeris. The system is a formal structure applied to a birth time, and its authority is traditional rather than observational.

The stars travel in fixed groups

A great deal of Zi Wei reading comes from the fact that certain stars are permanently locked in relation to each other. 七殺, 破軍 and 貪狼 always sit at 120° — find one and you know where the other two are. Because of these fixed relationships, a chart is read in triangles and axes rather than palace by palace.

Brightness: 廟旺得利平不陷

Every major star is graded for how well it sits in the branch it landed in, on a seven-step scale from 廟 (exalted) down to 陷 (fallen). The grading is a property of the star-and-branch pair, so it is fully determined once the chart is drawn — there is no interpretation involved in producing it, only in reading it.

The opposite palace, and borrowing

Every palace is read together with the palace directly facing it, six positions away. Roughly half of all charts have at least one palace with no major star in it at all; such a palace is not empty in practice, it borrows the stars from the palace opposite. A chart with an empty Life palace is completely normal and is read through what sits across from it.

What a birth hour changes, and what it doesn't

Zi Wei is considerably more hour-sensitive than BaZi. Without a birth hour you cannot reliably place the Life palace, which means the entire grid is unfixed and the reading is not merely less detailed but structurally unavailable. If you do not know your hour, BaZi will give you more that is trustworthy than Zi Wei will.

The twelve palaces

Every chart has these twelve, always in this order. The Life palace is located first from the birth month and hour; the rest follow from it.

PalaceWhat it covers
Life 命宮The palace the whole chart is read from. Temperament, the shape of a life, the person's default setting.
Siblings 兄弟Brothers and sisters, and by extension peers, colleagues and the people you stand level with.
Spouse 夫妻Marriage and long partnerships — both what you look for and what you tend to attract.
Children 子女Children, but also what you produce and pass on: students, projects, the next generation of anything.
Wealth 財帛How money arrives and how it behaves once it does. Not how much.
Health 疾厄Constitution and the body's habitual weak points; also stress and how it lands.
Travel 遷移Movement, being away from home, and how you are received by strangers.
Friends 僕役Subordinates, staff, wider social circle — the people who are neither peers nor family.
Career 官祿Work, position and reputation. Historically the palace of office-holding.
Property 田宅Land, home and the physical places you accumulate; also family stability.
Fortune 福德Inner life — what actually makes the person content, and what they enjoy spending on.
Parents 父母Parents and elders, and by extension bosses, mentors and institutional authority.

The brightness scale

Seven steps, strongest first. The grade is fixed by the star-and-branch pair, so producing it involves no interpretation — only reading it does.

GradeMeaning
ExaltedThe star is in its own temple. Everything it is good at works with the least friction here — and so does everything it overdoes.
StrongClearly well placed. The star's qualities show plainly and hold up under pressure.
FavourableComfortable but not commanding. The star works, without the surplus that exalted placements bring.
AdvantageousWorkable. The star gets its job done, usually by leaning on whatever else is in the palace.
NeutralNeither helped nor hindered. The reading depends almost entirely on the company the star keeps.
WeakThe star is out of its element. Its strengths are muted; its habits are not.
FallenThe hardest placement. Classically read not as failure but as the star's qualities arriving in the wrong form — the drive without the direction, the sharpness without the target.
Two caveats about every brightness table on this site. Two honest notes about the table above. First, brightness tables are not universal — Zi Wei Dou Shu has several living lineages, and they do not fully agree on the grading of every star in every branch. The table here is the one built into iztro, the open-source engine that draws the charts on this site, so it matches exactly what this tool will show you and does not claim to be the only tradition. Second, brightness describes the star's condition in that position, not the quality of the life. A fallen star in the Life palace is a description of how its qualities arrive, not a verdict, and plenty of consequential charts are built on fallen placements.

The four star groups

Certain stars are locked in fixed relation to each other, which is why charts are read in triangles and axes rather than one palace at a time.

The establishment group — 紫府廉武相

紫微 · 天府 · 廉貞 · 武曲 · 天相

Five stars concerned with position, structure and holding things together. They read as authority, administration and accumulated resource. Charts weighted here tend to build institutions, or work comfortably inside them.

The upheaval axis — 殺破狼

七殺 · 破軍 · 貪狼

These three always sit 120° apart, so they are permanently in each other's company — wherever one is, the other two are triangulated to it. Together they are the chart's appetite for change: the drive to break, rebuild and want. Lives weighted here move in cycles rather than lines.

The support group — 機月同梁

天機 · 太陰 · 天同 · 天梁

Classically the civil-service combination — the stars of thinking, tending, easing and sheltering. They do their best work in a defined role with something worth protecting, and their common failure is drift when nothing is asked of them.

The exposure pair — 巨日

太陽 · 巨門

Light and the gate it shines through. Both stars are about being seen and being heard — one by giving out, one by speaking up — and both carry the cost of visibility: exhaustion for one, dispute for the other.

The fourteen major stars

How this site calculates it, and where the method stops

This site draws its charts with iztro, an open-source Zi Wei engine, from the solar date and hour you enter. Star placement and the brightness grading both come from that library, so the tables on these pages match what the tool shows you rather than a second opinion pasted alongside it. What the site does not attempt is the interpretive layer that a practitioner supplies: the interaction between palaces, the four transformations (四化) as they move through the luck cycles, and the weighing of minor stars against major ones.

What a single star cannot tell you:

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