What is BaZi good for?

Structural questions: strengths and weak spots, where the elements lean, which phase favours a push, and what kind of person or setting fits. It is not for “what happens on a given day”.

Can I make decisions from this chart?

For reference only — not a substitute for medical, legal, or financial advice. BaZi shows structure and pace. It does not make the medical, legal or financial decision for you.

Do I need an exact birth time?

The two-hour branch sets the hour pillar, and the Ten Gods that hang on it. If the time is unknown, read the year, month and day, and leave the hour pillar blank. Do not guess a branch just to fill eight characters. If the birthplace longitude is far from its standard meridian, also check whether true solar time crosses an hour boundary.

The same birth details, timezone and day-boundary switch produce the same chart again. Stems, branches and weights can be checked line by line. That means the chart can be reproduced. It does not mean a judgment about one event has been confirmed.

What is the difference between a regular, formed and broken structure?

A regular structure is the ordinary month-command frame. A hidden stem that appears on a stem takes priority; otherwise the primary stem is used, giving names such as Direct Officer, Seven Killings, Wealth, Resource or Output. Formed asks whether the support that structure needs is present. Broken asks whether a key condition is disrupted by a clash or a control. This site lists the name and the evidence. It does not grade formed or broken as success or failure, and the name is not a rank.

Does true solar time always change the pillars?

No. True solar time corrects clock time by the birthplace longitude and the equation of time. A pillar changes only when the corrected time crosses an hour, a day boundary or a solar term. If it does not cross, the pillars stay as they were.

Do the lunar calendar and a leap month change the month pillar?

Yes. A lunar date, including its leap-month flag, is converted to the Gregorian date before the month pillar is set by the solar terms. The month pillar is not the lunar month itself. An unmarked leap month is treated as an ordinary month, and the month pillar is wrong from that step. Use the calendar in the birth record, and mark a leap month when it is one.

Why do two calculators disagree?

First match the year boundary (Beginning of Spring or not), the day boundary (23:00 or 00:00), how the hours are cut, and whether true solar time is on. If those switches differ, the pillars differ. The settings are listed under BaZi.

What if I cannot read the chart?

Name the day master, then see where the Ten Gods fall, then which element is heavier, and only then the luck cycle. Stop at the item that does not match. Do not let one structure name cover the stems and branches already printed.

How is the chart different from the AI reading?

The chart computes the pillars, Ten Gods, hidden stems, element strength, the strength score, the structure and the luck cycles from the chosen rules. The same input always matches. The AI reading only explains fields already calculated. It does not invent a missing birth time, and it does not treat a disputed call as the only fact. If the fields do not match, compare the chart before the reading.

BaZi · Four Pillars

Cast a free BaZi chart from your birth date and birthplace

The historical timezone is restored, the month pillar follows the solar terms, then the day master, Ten Gods and hidden stems are set. You can read the chart, or keep asking about one specific matter.

Four pillars
Ten Gods
Hidden stems
Element strength
Luck cycles

No sign-in required

Needs · Date and time of birth (true solar time by default)

DAY MASTERYi Woodweak · Officer

A BaZi chart in three steps

First, enter the birth details. Choose the Gregorian or lunar calendar, then gender, date, time and birthplace. If the lunar date is a leap month, mark it. What remains is a frozen birth record. Every pillar comes from it.

Second, restore the clock time. The chart takes the timezone and daylight saving of the birthplace in that year, then applies longitude and the equation of time if you turn that switch on. Mainland China returns to UTC+9 in the summers of 1986 to 1991. Each correction stays on the chart so you can check it.

Third, the chart is cast. The four pillars, Ten Gods, hidden stems, element strength, strength score, structure and ten-year luck cycles are computed in the same pass. The AI explains only fields already on the chart. It does not move a pillar, and it does not fill in a birth time you left blank.

What a BaZi chart needs

Five items: birth date, birth time, birthplace, gender and calendar. Without the hour, the hour pillar cannot be set, and the Ten Gods on it are not reliable. One branch off is not a single character off. The Ten Gods on the hour pillar change with it.

If you live abroad and were born in China, the place is still the birthplace. The timezone follows the birthplace, not the city you live in now. The wrong timezone can shift the hour pillar by one branch.

True solar time does not always change the pillars. It corrects clock time by longitude and the equation of time. A pillar changes only when that correction crosses an hour, a day boundary or a solar term. If it does not cross, the pillars stay as they were.

Mark a lunar leap month. Unmarked, it is treated as an ordinary month, the Gregorian date is already wrong, and the month pillar follows. If the birth record says leap month, mark it.

If these fields are still unclear, start with what BaZi is.

How a BaZi chart is calculated

The chart turns this submission into a result you can calculate again. The input is calendar, date, time, birthplace and gender. The output is the four pillars, day master, Ten Gods, hidden stems, element strength, strength score, structure, seasonal adjustment, void branches, twelve stages, nayin, and the ten-year luck cycles with annual pillars. Match those fields before you read the commentary.

Restore the clock, then decide on the correction

Clock time is restored first to the timezone and daylight saving of the birthplace in that year. Most years in mainland China are UTC+8. The summers of 1986 to 1991 go back to UTC+9. This step does not move a stem or a branch. It only fixes the local clock time of that moment.

True solar time is the optional next correction. The birthplace longitude, measured from the standard meridian, plus the equation of time, gives the Sun’s position. A pillar changes only when the corrected clock crosses an hour, a day boundary or a solar term. The switch and each correction stay on the chart.

The pillars are cut on four boundaries

The year changes at Beginning of Spring, not on 1 January. The month changes at the twelve solar terms, so it is neither the Gregorian month nor the lunar month. The day is taken by the day-boundary rule, 23:00 by default, or 00:00 if you switch it. The hour is one two-hour branch.

A lunar date, leap month included, is converted to the Gregorian date before those boundaries are applied. An unmarked leap month is converted as an ordinary month, and the month pillar differs from there.

Ten Gods, hidden stems and elements come after the pillars

The day stem is the day master. The other stems become Ten Gods against it. Each branch splits into primary, middle and residual stems, weighted 1, 0.5 and 0.3. Those weights enter the element counts, and each hidden stem is also a Ten God. The names on the chart are Friend, Rob Wealth, Eating God, Hurting Officer, Indirect Wealth, Direct Wealth, Seven Killings, Direct Officer, Indirect Resource and Direct Resource.

The strength score adds and subtracts along season, rooting and support, and prints each line. The structure is the stem that can stand in the month command. Seasonal adjustment is a separate line for the cold, heat, dryness or damp of that month. These are readings after the pillars are fixed. They do not go back and change a stem or a branch.

Luck cycles use the distance to a solar term, and a direction

The wait before the first cycle is the distance from birth to the neighbouring solar term, written as years and months, with a start date beside it. Direction follows the year stem’s yin or yang and the gender. A yang year with a man, or a yin year with a woman, runs forward. A yang year with a woman, or a yin year with a man, runs backward.

Each luck cycle is ten years, with a stem, a branch and a Ten God. The annual pillar is the shorter layer inside that decade, stacked on the natal chart. It is not a second set of four pillars. The AI explains only fields already calculated. It does not invent an hour you left blank, and it does not change the pillars.

How to read the chart you cast

What you see after casting is calculated, and you can check it line by line. Match the field on the chart first, then read the note beside it. No luck grade is added here.

Pillars and day master: the year, month, day and hour pillars sit at the top. The day stem is the day master. The other seven characters are read against it.
Ten Gods and hidden stems: each stem is labelled with a Ten God. Under each branch are the primary, middle and residual stems, weighted 1, 0.5 and 0.3. Read the primary first, then the two lighter layers.
Element strength and the score: the elements are weighted counts, not a tally of the eight characters. Under the strength score, every plus and minus is listed.
Structure and seasonal adjustment: the structure names the stem that stands in the month command, with its evidence. Seasonal adjustment is a separate line for that month. Do not merge the two lines into one verdict.
Void, the twelve stages and nayin: void marks the two branches missing from this cycle, the stages mark where the day master stands, and nayin is the tone of a stem-branch pair. All three are supplementary.
Luck cycles and annual pillars: a luck cycle is ten years, with its stem, branch, Ten God and the years it covers. Annual pillars sit inside that step. They do not open a second natal chart.
The settings used this time: whether true solar time is on, which solar term was used, whether the day boundary is 23:00 or 00:00, and the birthplace timezone, all stay on the chart.

If a Ten God does not match, see Ten Gods and hidden stems. If an element does not match, see element strength. If a luck-cycle age does not match, see luck cycles. If void, the stages or nayin do not match, see void, stages and nayin.

One worked BaZi example

This example shows where each field sits. It is not a judgment of a person, and the score is not written as character or fortune. The input is lunar 8th day of the leap 5th month, 1990, at 21:40, female, birthplace Beijing, timezone Asia/Shanghai, day boundary 23:00, true solar time on.

The calendar line shows “lunar” and “leap month”. The Gregorian date is 1990-06-30. Without the leap-month mark it would be treated as the ordinary 5th month, and both the Gregorian date and the month pillar would differ from this step. The timezone line shows +09:00 for that summer: standard time +08:00, plus one hour of daylight saving. That is how mainland China is restored for the summers of 1986 to 1991.

The true-solar-time line lists the longitude correction and the equation of time. In this example the corrected clock time is 20:22. The entered 21:40 falls in Hai. 20:22 falls in Xu, so the hour pillar crosses an hour boundary. When a correction does not cross a boundary, the hour pillar stays as it was. To keep this chart, look first at whether true solar time is on or off.

The pillar line prints Geng-Wu, Ren-Wu, Bing-Yin and Wu-Xu (庚午, 壬午, 丙寅, 戊戌). The day master is the day stem, Bing. The Ten Gods sit beside the stems: year stem Geng is Indirect Wealth, month stem Ren is Seven Killings, and hour stem Wu is Eating God. Hidden stems sit under the branches. The day branch Yin, for example, is primary Jia, middle Bing and residual Wu, weighted 1, 0.5 and 0.3.

The element line is the weighted count, not a tally of the eight characters. In this example Fire is 3.8, Earth 3.3, Metal 1.5, Wood 1 and Water 1. The strength line gives a score and lists each plus and minus, including whether the month branch’s primary stem, the day branch’s hidden stems and the year stem add or subtract. The score is the total of those lines. It is not an evaluation of the person.

The luck-cycle line starts with the wait before the first cycle. In this example that is 8 years, 2 months and 10 days, with the start date printed beside it. Year stem Geng is yang and the gender is female, so this example runs backward. The first cycle is Xin-Si. Annual pillars sit inside that decade; 1998, for example, is marked Wu-Yin. They do not replace the four pillars. How the start and the ages are derived is in luck cycles.

When two charts do not match

If another calculator disagrees, check in this order: the year boundary (Beginning of Spring or not), the day boundary (23:00 or 00:00), how the hours are cut, then whether true solar time is on. Do not reverse the order. Comparing two BaZi charts before the timezone, true solar time and day boundary are aligned is not a comparison of the same chart.

A different year boundary changes the year pillar. A different day boundary changes the day pillar around 23:00. A different hour cut changes the hour pillar. True solar time changes a pillar only when it crosses a boundary. Off and on can be two charts.

Where those switches sit in the glossary: BaZi.

What to read next

If the pillars and Ten Gods are still unclear, start with what BaZi is. For the terms in detail, start with the four pillars.

The BaZi chart on fatequery

The BaZi chart on fatequery is an online casting for people studying the method. Enter a birth date, time and birthplace and the chart is cast. You can keep the chart, continue with the AI reading, or fill in the pillars and Ten Gods from the glossary.

The reading is done by an AI built for BaZi. It reads the pillars already cast, starting from the day master, then the Ten Gods, hidden stems, element strength, strength score, structure, seasonal adjustment, luck cycles and annual pillars. The conclusion comes first. The evidence follows.

Casting a chart, studying one, and questions about temperament, work, money or a relationship can all be used as a reference. If you are not sure what to ask, start with what BaZi is.

Common questions

What is BaZi good for?: Structural questions: strengths and weak spots, where the elements lean, which phase favours a push, and what kind of person or setting fits. It is not for “what happens on a given day”.
Can I make decisions from this chart?: For reference only — not a substitute for medical, legal, or financial advice. BaZi shows structure and pace. It does not make the medical, legal or financial decision for you.
Do I need an exact birth time?: The two-hour branch sets the hour pillar, and the Ten Gods that hang on it. If the time is unknown, read the year, month and day, and leave the hour pillar blank. Do not guess a branch just to fill eight characters. If the birthplace longitude is far from its standard meridian, also check whether true solar time crosses an hour boundary.
Is BaZi accurate?: The same birth details, timezone and day-boundary switch produce the same chart again. Stems, branches and weights can be checked line by line. That means the chart can be reproduced. It does not mean a judgment about one event has been confirmed.
What is the difference between a regular, formed and broken structure?: A regular structure is the ordinary month-command frame. A hidden stem that appears on a stem takes priority; otherwise the primary stem is used, giving names such as Direct Officer, Seven Killings, Wealth, Resource or Output. Formed asks whether the support that structure needs is present. Broken asks whether a key condition is disrupted by a clash or a control. This site lists the name and the evidence. It does not grade formed or broken as success or failure, and the name is not a rank.
Does true solar time always change the pillars?: No. True solar time corrects clock time by the birthplace longitude and the equation of time. A pillar changes only when the corrected time crosses an hour, a day boundary or a solar term. If it does not cross, the pillars stay as they were.
Do the lunar calendar and a leap month change the month pillar?: Yes. A lunar date, including its leap-month flag, is converted to the Gregorian date before the month pillar is set by the solar terms. The month pillar is not the lunar month itself. An unmarked leap month is treated as an ordinary month, and the month pillar is wrong from that step. Use the calendar in the birth record, and mark a leap month when it is one.
Why do two calculators disagree?: First match the year boundary (Beginning of Spring or not), the day boundary (23:00 or 00:00), how the hours are cut, and whether true solar time is on. If those switches differ, the pillars differ. The settings are listed under BaZi.
What if I cannot read the chart?: Name the day master, then see where the Ten Gods fall, then which element is heavier, and only then the luck cycle. Stop at the item that does not match. Do not let one structure name cover the stems and branches already printed.
How is the chart different from the AI reading?: The chart computes the pillars, Ten Gods, hidden stems, element strength, the strength score, the structure and the luck cycles from the chosen rules. The same input always matches. The AI reading only explains fields already calculated. It does not invent a missing birth time, and it does not treat a disputed call as the only fact. If the fields do not match, compare the chart before the reading.