FAQ
BaZi Calculator FAQ
These are the questions people ask most often about calculating a BaZi (Four Pillars) chart on this site. Each answer explains the rule we follow and where to change it.
Open the tool in another tab to follow along.
01
Quick answers
| Question | Short answer |
|---|---|
| What do I need to calculate a BaZi chart? | Birth date, birth time if known, and birth city. |
| I don't know my birth time. Can I still use it? | Yes. |
| Why is my year pillar different from my Chinese New Year year? | BaZi changes year at 立春 (around 4 February), not at the lunar New Year. |
| Why does the month pillar not match the lunar month? | BaZi months start at the twelve 节 solar terms; lunar months start at new moons. |
| What is true solar time and should I use it? | It corrects clock time for longitude and the equation of time. |
| I was born after 23:00. Which day am I? | By default the day changes at 23:00 (the Zi hour). |
| How is the starting age of luck pillars calculated? | From the time between birth and the neighbouring 节 solar term, at three days per year. |
| Is my birth data stored? | Calculations run without an account. |
| Can I export or print my chart? | Yes: print, save as PDF from the print dialog, or download JSON for your own records. |
| Is BaZi scientifically proven? | No. |
02
Key terms
- Four PillarsThe Four Pillars are the year, month, day and hour of birth, each written as a heavenly stem over an earthly branch.
- Day MasterThe Day Master (日主 or 日元) is the heavenly stem of the day pillar.
- True Solar TimeTrue 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).
- Start of Spring (Li Chun)立春, when the sun reaches 315° ecliptic longitude around 4 February, begins the BaZi year and the 寅 month.
03
Practising with BaZi Calculator
The fastest way to understand BaZi Calculator is to look at real charts rather than memorise rules. Enter a birth date, time and city in the BaZi Calculator, then locate where BaZi Calculator appears: in a visible stem, hidden inside a branch, in the current luck pillar or in this year's annual pillar. Note the position, because the year pillar is usually read as background and early life, the month pillar as environment and career setting, the day pillar as the self and close partner, and the hour pillar as later life and output.
- Compare two or three charts where BaZi Calculator is prominent and two where it is absent; write down what differs in the overall balance.
- Check the month branch first: seasonal strength changes how much any factor matters.
- Use the hidden-stems and Ten Gods tables in the calculator output instead of guessing.
- Treat single factors as clues, never as verdicts; classical texts always weigh the whole chart.
Different schools describe BaZi Calculator with slightly different emphasis. This site follows widely used conventions (solar-term months, true solar time optional, Zi hour setting configurable) and states them openly so you can compare results with a book or another calculator.
04
A suggested study path
BaZi Calculator is one piece of a larger system. If you are learning BaZi from scratch, the order below builds each idea on the previous one, and every step links to free reference pages on this site.
- Calculate a chart and confirm the four pillars are correct (checklist).
- Learn the ten heavenly stems and twelve earthly branches.
- Find your Day Master and judge its strength with the five elements.
- Read the Ten Gods in context.
- Move on to timing with luck and annual pillars.
- Use the glossary whenever a term is unfamiliar.
05
Scope
Charts on this site use the published rule set: true solar time by default, the year changes at 立春 (Start of Spring), months change at the 12 节 solar terms and the day changes at 23:00. Example charts below are computed live by the same engine.
BaZi is a traditional cultural system. This page explains how the symbols are defined and read; it does not make scientific claims or predictions about your health, money or relationships.
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