What is BaZi (the Four Pillars of Destiny)?

BaZi, or the Four Pillars of Destiny, is the core method of classical Chinese astrology. A person's birth year, month, day and hour are each expressed as a Heavenly Stem paired with an Earthly Branch — eight characters in total ("BaZi" = "eight characters"), arranged in four pillars ("Si Zhu"). The Day Stem is the Day Master, representing the person; the relationships (Ten Gods), hidden stems, melodic elements, symbolic stars, and luck pillars among the other characters form a complete system of analysis rooted in classics such as Zi Ping Zhen Quan and Di Tian Sui.

Are "Four Pillars", "birth eight characters" and "Zi Ping" the same thing?

Yes — they are different names for one tradition. "Four Pillars" stresses the year/month/day/hour structure, "birth eight characters" stresses the birth time as the source, and "Zi Ping" refers to the day-master-centred method established by Xu Ziping in the Song dynasty. Modern BaZi charting follows this Zi Ping orthodoxy, as does this tool.

What are the Ten Gods, and why are they central to BaZi?

The Ten Gods describe how every other stem and branch relates to the Day Master by the five-element cycle and yin/yang: Friend & Rob Wealth (same as self), Eating God & Hurting Officer (output), Direct & Indirect Wealth (what self controls), Direct Officer & Seven Killings (what controls self), Direct & Indirect Resource (what generates self). They translate abstract element relations into human meaning (wealth, authority, resource, expression) and drive structure, success and the choice of the favourable element.

How is the strength of the Day Master judged?

Strength depends mainly on whether the Day Master is supported by the month branch (the seasonal command), reinforced by stems and rooted in branches, balanced against what drains or controls it. A strong Day Master favours output, wealth and authority to balance it; a weak one favours resource and peers. The tool tallies element energy and Ten-God strength to help you judge.

What are hidden stems, and why list them?

Each Earthly Branch hides 1–3 Heavenly Stems (the "human element"), e.g. Yin hides Jia/Bing/Wu. Hidden stems carry primary, middle and residual qi and define a branch's true element and Ten-God content. The commanding hidden stem of the month branch is decisive for structure and the favourable element, so a professional chart always lists them.

What are the melodic (NaYin) elements?

NaYin assigns one of thirty melodic elements to each pair of the sixty Jia-Zi (e.g. Jia-Zi/Yi-Chou = "Gold in the Sea"). NaYin is used in compatibility, date selection and some schools' analysis, alongside the regular elements. The tool labels NaYin for all four pillars and the luck pillars.

Are the symbolic stars (ShenSha) reliable?

Symbolic stars are auxiliary markers — auspicious (Nobleman, Academic Star, Travelling Horse, Peach Blossom…) and inauspicious. The classical view treats structure and the Ten Gods as primary and stars as secondary: alone they are limited, but combined with structure and luck pillars they add nuance and warnings. The tool lists the mainstream stars by tier.

How are luck pillars arranged? What is the starting age?

Luck pillars derive from the month pillar, running forward or backward by the yin/yang of the year and the sex, each governing ten years. The starting age comes from the days between birth and the adjacent solar term divided by three. The tool determines the direction automatically, computes the exact start age, and links annual, monthly and daily luck.

What are the Life Palace, Body Palace and Fetal Origin?

The Life Palace (from month and hour branches) marks innate disposition; the Body Palace (from day and hour branches) marks lived experience; the Fetal Origin (derived from the month pillar) marks conception. With the four pillars they form the "seven pillars" used in advanced analysis — all generated automatically here.

What does "void" (KongWang) mean?

Within each ten-stem cycle two branches are left without a stem — these are the "void" branches of that day pillar. Forces falling on a void position are often reduced, to be re-weighed against clashes, combinations and "filling". The tool marks void branches from the day pillar's cycle head.

What is the chart structure (GeJu), and how is the favourable element chosen?

Structure is the core pattern, based on what the month branch's hidden stems reveal — normal structures (Officer, Killings, Wealth, Eating, Hurting, Resource) and special ones (Lu, Yang Blade, Follow, Transformation, Dominance…). The favourable element balances the chart through strength, climate and mediation. The tool applies Zi Ping Zhen Quan structure rules, Qiong Tong Bao Jian climate use and strength heuristics for a reference verdict.

What is the climatic favourable element (TiaoHou)?

Climate balances the chart by the season's cold/warm/dry/damp: winter births often need fire to warm, summer births water to moisten. Qiong Tong Bao Jian lists the climatic element for each "day stem + month" combination. The tool matches the relevant passage automatically.

Why correct to true solar time?

BaZi depends on an exact hour. China uses one standard time (120°E) but spans ~73°E–135°E, so local solar time can differ by over an hour. Near a pillar boundary — especially the Zi-hour day change at 23:00/01:00 — true-solar-time correction can change the hour or even day pillar. The tool offers longitude + equation-of-time correction in one click.

What is the difference between solar, lunar and eight-character input?

Three input modes are supported: solar (Gregorian) date is the most common; lunar date is converted to solar automatically, with leap months; and if you already know the four pillars you can enter them to reverse-look-up the date. All three produce the same chart — pick whichever you have.

Is this Four Pillars chart tool free? Do I need an account?

It is fully free with no sign-up: four pillars, Ten Gods, hidden stems, NaYin, symbolic stars, luck pillars, element strength, structure, climatic use and true-solar-time correction are open to everyone. Signing in adds cloud saving, cross-device sync and per-year notes.

Is online BaZi charting accurate?

Charting is deterministic astronomical/calendar computation: stems, hidden stems, NaYin, stars, luck-pillar start and the palaces are computed precisely and reliably. Note that charting is objective, while interpretation (verdicts, choice of favourable element) belongs to differing schools — the structure and favourable element shown here are for study only.

Can I save or share a chart?

Yes. After charting you can export JSON, generate a share link or save a poster image; signed-in users can store charts in the cloud, recall them from history and add per-year notes for long-term tracking.

BaZi Calculator · Four Pillars of Destiny

Free online BaZi chart — stems & branches, Ten Gods, hidden stems, NaYin, symbolic stars, luck pillars, element strength and structure

Gender

Input mode

Four Pillars 四柱

Year

Month

Day

Hour

No matching date (stem-branch combination is impossible)

Enter your birth details, then tap “Cast chart”

Your Four Pillars (BaZi) chart will appear here

What is BaZi (the Four Pillars)?

BaZi, the Four Pillars of Destiny, is the core method of classical Chinese astrology. A person's birth year, month, day and hour each form a "pillar" of one Heavenly Stem and one Earthly Branch — eight characters in total. The Day Stem is the Day Master, representing the person; the other seven characters interact with it through the five-element cycle to form a complete natal chart.

A professional Four Pillars chart shows not only the eight characters but also the Ten Gods, hidden stems, NaYin elements, voids, the twelve life stages, symbolic stars, luck pillars, element strength, the Life/Body Palaces and Fetal Origin, plus structure and climatic favourable elements. This tool computes all of them at once, supports solar, lunar and eight-character input with true-solar-time correction, and is free with no sign-up.

How to chart BaZi: four steps to your natal chart

Charting is deterministic calendar computation — these four steps let you read any BaZi chart.

1
① Fix the birth time
BaZi rests on an exact hour. For cross-region or boundary Zi-hour (23:00/01:00) births, correct longitude with true solar time first.
2
② Lay out the four pillars
Set the month pillar by the 24 solar terms and the hour stem from the day stem to get all eight characters.
3
③ Annotate the elements
List the Ten Gods, hidden stems, NaYin, voids, life stages and stars for each pillar, and tally element strength.
4
④ Luck pillars & favourable element
Arrange luck pillars by yin/yang direction, compute the start age, then judge the favourable element from structure and climate.

Every step above is automated here — enter your birth details and tap "Chart" to get the full result at once: pillars, Ten Gods, hidden stems, NaYin, stars, luck pillars, element strength and structure.

What a BaZi chart shows: the ten core elements

Understand these ten elements and the whole Four Pillars chart opens up.

Stems, Branches & the Four Pillars: Ten Heavenly Stems and twelve Earthly Branches pair into the sixty Jia-Zi. Year, month, day and hour each take one pair — the four pillars, the skeleton of the chart.
Day Master & the Ten Gods: The Day Stem is the Day Master. Measured against it, the other characters yield the Ten Gods (Friend, Rob Wealth, Eating God, Hurting Officer, Wealth, Officer, Killings, Resource…), which drive structure and analysis.
Hidden Stems: Each branch hides 1–3 stems (primary, middle, residual). The commanding stem of the month branch is decisive for structure and the favourable element.
NaYin Elements: Each pair of the sixty Jia-Zi carries a NaYin element (e.g. Gold in the Sea), thirty in all, used in compatibility, date selection and analysis.
Symbolic Stars (ShenSha): Auspicious stars (Nobleman, Academic, Travelling Horse, Peach Blossom…) and inauspicious ones add nuance and warnings alongside structure — treated as secondary in the classics.
Luck Pillars & Annual Luck: Luck pillars run from the month pillar, ten years each; the annual pillar interacts with the chart to shape each period. The tool links annual, monthly and daily luck.
Element Strength & Favourable Element: Judge the Day Master's strength from the season, roots and stems, then choose the favourable and unfavourable elements by strength, climate and mediation.
Chart Structure: The month branch defines normal and special structures (Officer, Killings, Wealth, Eating, Hurting, Resource, Lu, Yang Blade, Follow, Transformation…), whose success sets the chart's level.
Void & Life Stages: Voids (two stem-less branches from the day pillar's cycle) weaken forces that land on them; the twelve life stages (Birth, Bath … Peak … Tomb, Death) gauge a stem's state within a branch.
Life / Body Palace & Fetal Origin: The Life Palace (month + hour), Body Palace (day + hour) and Fetal Origin form the "seven pillars" with the four pillars — auxiliary coordinates for advanced reading.
True Solar Time: China uses one standard time (120°E) yet local solar time can differ by over an hour. Boundary Zi-hour births especially need true-solar-time correction.
Classical Sources: Structure follows Zi Ping Zhen Quan and climatic use follows Qiong Tong Bao Jian, with reference to Di Tian Sui, San Ming Tong Hui and Yuan Hai Zi Ping.

FAQ

Four Pillars (BaZi) Chart — FAQ

延伸阅读

名人命例与流年通览，都可一键回到排盘工具对照。

名人八字命例

帝王将相、文臣名士的四柱与十神，附生辰出处与可靠度。

2026 年流年运势 · 十日主分论

按日主看今年太岁十神：事业、财运、感情逐项解读。

Related charting tools

Beyond BaZi charting, these tools share the same Four Pillars roots.

True Solar Time

Longitude + equation-of-time correction — the essential step before BaZi charting.

Ganzhi Kaleidoscope

Stems & branches at a glance: sixty Jia-Zi, relation wheel, life-stage matrix, NaYin.