Four Pillars chart
Enter birth time for stems, branches, and elements.
1About
BaZi, or the Four Pillars of Destiny, describes a birth moment with one heavenly stem and one earthly branch for each of the year, month, day and hour: eight characters in total. The day stem is the Day Master, the reference point for the Ten Gods.
This tool uses the open-source lunar-javascript library to calculate the pillars, hidden stems, Na Yin, Ten Gods and surface element counts, plus the annual pillar for this year or next. Readings describe the chart's structure as a cultural reference, not a scientific forecast.
2How it works
Four Pillars uses Beginning of Spring for the year and solar terms for months. The selected day boundary applies. Zi Wei uses iztro default stars, lunar New Year, and adjusted leap months: days 1–15 use the current month, later days the next. Schools may differ. Engines: lunar-javascript and iztro.
3How to use
- Enter your details in the form on the left (a date, number or name). Fields marked optional can be skipped.
- Press the button; the result is worked out instantly in your browser and shown in the middle.
- Treat the result as a reference; change an input and run it again to compare.
4Privacy & data
Tools still work without registering. Optional social sign-in (Google, Facebook or LINE) may receive an account id and sometimes email or display name from that provider; we do not create passwords, and sign-in never uploads birth details or charts. Birth details remain in page memory and are removed on clear or reload. They are not stored or added to URLs. Only language preference is saved locally. The site is funded by ads: pages load a Monetag MultiTag, plus an Adsterra Social Bar (a corner overlay). These scripts run on the page itself. Adsterra, Monetag and their partners may receive your IP and browser information and use cookies for ad delivery and measurement (Adsterra privacy policy: https://adsterra.com/privacy-policy/). We do not deliberately provide birth details or charts to advertisers, but we cannot prevent a third-party script from reading the page; use your browser's ad blocking if this concerns you. Each move to another page is a full page load. Visitors in the EEA, UK or Switzerland must agree before ads load. No analytics or external AI requests are enabled. You can refuse ads with your browser's ad or cookie blocking; the tools keep working.
5FAQ
What do I need to calculate a BaZi chart?
Your Gregorian birth date and birth time in UTC+8 standard time. Without a birth time you still get the year, month and day pillars, plus a table of all twelve possible hour pillars.
When do the BaZi year and month change?
The year changes at Beginning of Spring (Lichun, around February 4) and months change at solar terms, not at Lunar New Year or January 1.
How is a birth between 11 pm and midnight handled?
Schools differ. By default the day changes at midnight; the alternative late-Zi rule starts the next day at 11 pm. You can switch between them in the form.
I was born outside UTC+8. Can I use it?
UTC+7 (Vietnam, Thailand) and UTC+9 (Japan, Korea) can be selected directly and are converted automatically. For other places, convert your birth time to UTC+8 first. Historical daylight saving time and true solar time are not handled.
Is my birth data uploaded or stored?
No. Everything is calculated in your browser and kept only in page memory; clearing or reloading removes it.
How do I check my 2027 (Ding-Wei) yearly fortune?
The BaZi tool shows this year and next year's stem-branch and Ten Gods. For Tai Sui, flying stars and lucky days, open the 2027 year guide and enter your birth details for a personal yearly forecast.
What is the Day Master and how do I read a BaZi chart?
The Day Master is the heavenly stem of the day pillar (the third pillar) and stands for you in the chart. The other stems and hidden stems are described as Ten Gods by their relationship to it (for example Resource, Output or Wealth), and the five-element counts show which elements are strong or weak. This tool lists these for you; it describes the structure of the chart as a cultural reference, not a prediction.
Does it work for Singapore, Malaysia, Hong Kong, Taiwan and China?
Yes. These places use UTC+8, so enter your birth time as written on the birth certificate. Historical daylight saving time and true solar time are not handled, and Singapore and peninsular Malaysia used UTC+7:30 before 1982, so for earlier births convert the time to UTC+8 first.