Professional Zi Wei Dou Shu Calculator

Accurate calculation of the 12 Palaces chart and the dynamics of the Four Transformations across Decades and years.

FOUNDATION FOR STRATEGY AND THE 12 PALACES

Zi Wei Dou Shu (紫微斗数) is a foundational system of Chinese astrology that structures the life chart across 12 Palaces.

Designed for professional practitioners, the Qi Chart calculator eliminates subjective interpretations by delivering pure mathematical calculations: precise coordinates for the Destiny and Body Palaces, the placement of the 14 major and auxiliary stars, brightness ratings, and the distribution of Transformations across three key layers — natal ('Birth'), 10-year cycles ('Decade'), and current periods ('Year').

ASTRONOMICAL ACCURACY AND SOLAR TIME

Generating a Zi Wei Dou Shu chart relies on calculating True Solar Time (TST). The algorithm automatically calculates the geographic offset based on the longitude of the birthplace and synchronizes the data with the traditional lunar calendar. The mathematical engine integrates solar terms (節氣) transitions and astronomical adjustments for the Equation of Time (EoT). This ensures the precise distribution of stars and eliminates boundary errors between two-hour Chinese double hours.

TIME DYNAMICS AND TRANSFORMATIONS

The control panel above the Zi Wei Dou Shu chart allows you to examine the birth chart not only statically, but also dynamically through life cycles: 10-year Decades (大限) and annual cycles (流年). The calculator recalculates the movement of the four key Transformations in real time: Prosperity (祿), Authority (權), Fame (科), and Obstacle (忌). This clearly highlights periods of career advancement, financial growth, or areas requiring heightened attention in any chosen phase of life.

SECURITY, EXPORT, AND PRINTING

The Zi Wei Dou Shu calculator fully implements Qi Chart's data protection standards. All calculations and saved charts remain strictly confidential. The 'Share' feature allows you to send interactive charts via encrypted links without disclosing personal data. For client consultations and reporting, one-click printing and vector PDF export in A4 format are supported.

Questions and Answers

Which day-boundary method should I choose: 23:00 or 00:00 (Early and Late Rat)? +

The double-hour of the Rat (子時) spans from 23:00 to 01:00 and is traditionally divided into the Late Rat (23:00–00:00) and the Early Rat (00:00–01:00). In classical tradition, two schools of thought exist: changing the calendar date at the beginning of the 子 hour (23:00 of the previous day) or at midnight (00:00 of the current day). The input form provides a '23:00 / 00:00' toggle, allowing you to choose the lineage canon of your practice. The selected setting is saved to your profile and ensures precision in determining the Destiny Palace (命宮).

How does the calculator handle birth dates that fall in a leap lunar month? +

When a birth date falls in an intercalary (leap) lunar month (閏月), the system offers three recognized methodologies for day distribution:

Days 1 to 15 belong to the current lunar month, while days from the 16th onward are assigned to the following lunar month;
Always current month: The entire leap period is assigned to the current month;
Always next month: All days of the leap month are assigned to the upcoming month.

Your preferred method can be saved in your Account Settings for automatic application in all future calculations.

What are the 'Birth / Decade / Year' toggles above the chart used for? +

This control panel manages the dynamic layer of the Transformations (祿, 權, 科, 忌):

- 'Birth' mode reveals the innate natal energies of the chart;
- 'Decade' mode activates 10-year luck pillars (大限) with age steppers, illustrating the shift of Transformations across the current decade;
- 'Year' mode calculates transit influences for the selected annual cycle (流年).

Switching between time layers happens instantaneously without refreshing the page.

Why should Equation of Time (EoT) be enabled during calculation? +

Traditional Chinese astrology is governed by the solar time at the exact location of the event rather than administrative clock time zones. The calculator determines the geographic longitude of the city, and the 'EoT' option applies an astronomical correction for the eccentricity of Earth's orbit (ranging from -14 to +16 minutes). This is critical for individuals born near the cusp of two double hours, where a few minutes' difference can alter the hour pillar, the Destiny Palace (命宮), and the entire stellar arrangement.

How do I save a chart or share a calculation? +

Registered users can save charts to their private cloud archive and attach personal notes. To share a chart with a client or colleague, simply use the 'Share' button: it generates a direct, encrypted link that opens the interactive chart on any smartphone or computer without requiring registration.