Zi Wei Dou Shu (紫微斗數)
Generate your 12-palace Zi Wei Dou Shu natal chart. Palace positions, major stars with brightness and four transformations (四化), and large-cycle limits (大限). Computed entirely in your browser.
Your Zi Wei Chart
Major stars shown with brightness (廟旺得利平不陷) and four transformations (化祿化權化科化忌). Numbers in the lower right of each palace are the large-cycle (大限) age range.
Your Zi Wei chart reveals palace positions and star configurations at the time of your birth. The Bazi Four Pillars chart reveals the elemental profile of your birth date and time. Both systems operate independently and can be read alongside each other.
New to the twelve palaces and major stars? The plain-English guide to Zi Wei Dou Shu walks through what each palace means, offered as a companion for reflection alongside your chart.
About This Chart
- ◆System: Zi Wei Dou Shu (紫微斗數) is a Chinese astrology system that uses the birth date, time, and gender to place 14 main stars and dozens of supporting stars across 12 palaces arranged around a fixed grid. Each palace governs a life domain such as career, wealth, relationships, health, and travel.
- ◆Calculation engine: Charts are computed using the open-source iztro library (v2.5.8) bundled locally. No data leaves your browser. The library implements the standard Zi Ping Zi Wei system with the 火鈴 star placement rules common in Taiwan and Hong Kong practice.
- ◆Hour index: The birth hour is converted to one of 13 Chinese time units (時辰). 00:00-01:00 is early Zi (早子時, index 0); 23:00-00:00 is late Zi (晚子時, index 12). The same local hour used by the Bazi calculator is applied here, including any True Solar Time correction if one was saved.
- ◆Gender and large cycles: Gender determines the direction of the large-cycle limits (大限). In the standard system, males in Yang years and females in Yin years run forward (順行); the reverse applies to males in Yin years and females in Yang years. The starting age is set by the five-elements class (五行局).
- ◆Four transformations (四化): Each birth year stem activates four transformations: 化祿 (prosperity), 化權 (authority), 化科 (recognition), and 化忌 (obstacle). These are shown as tags on the relevant stars in each palace.
- ◆What this is not: This chart shows structure and placement only. Reading a Zi Wei chart meaningfully requires comparing the natal chart against current large cycles, annual charts, and other factors. Use this as a starting reference, not a forecast.
How Does the Zi Wei Dou Shu Calculator Work?
The calculator takes your birth date, birth time, and gender, then converts the date to the Chinese lunar calendar and the time to one of the twelve double hours. Those two values determine where the chart begins. The system places Zi Wei, the purple star that gives the method its name, then positions the remaining thirteen major stars and dozens of supporting stars across twelve palaces arranged in a fixed grid. Each palace governs a domain of life such as career, wealth, health, relationships, or travel, and the stars sitting in a palace colour how that domain is traditionally read. Your birth year stem also activates four transformations, prosperity, authority, recognition, and obstacle, which attach to specific stars as tags. Gender sets the direction in which the ten year cycles run. Everything is computed in your browser. What you receive is structure and placement, a map of the chart rather than an interpretation of it. The correlative reasoning behind this kind of mapping is discussed in the Stanford Encyclopedia of Philosophy entry on Chinese metaphysics.
How Should You Use This Result?
Read the chart as a description to think with, not a forecast. A palace crowded with major stars does not promise success in that area, and an empty palace does not indicate absence. In traditional practice meaning emerges from relationships between palaces and from comparing the natal chart against current cycles, work this page does not attempt. One calendar point is worth knowing if you also use Bazi. Zi Wei reads the year from the lunar calendar, changing at Chinese New Year, whereas Zi Ping Bazi sets the year boundary at Li Chun, the solar term near February 4. A January or early February birthday can therefore fall in different years depending on which system you consult. Nothing here is fate, medical, financial, or professional advice. For a full reading, a qualified practitioner is the appropriate source.
What Is the Cultural Background?
Zi Wei Dou Shu, sometimes called Purple Star Astrology, is traditionally attributed to the Song dynasty figure Chen Xiyi, though the system as practised today took shape gradually across later centuries. It spread widely in Taiwan, Hong Kong, and Southeast Asian Chinese communities, where distinct lineages developed their own placement rules and reading conventions. Broader scholarly work on Chinese divinatory practice traces how such systems functioned socially, as ways of framing decisions and understanding character.