What is saju? Korea's four pillars (saju palja) explained

What does the word saju mean?

Saju (사주, 四柱) is a Korean word written with two Chinese characters: sa (四), "four", and ju (柱), "pillar". It is pronounced roughly SAH-joo. The four pillars are the year, month, day and hour of a person's birth. The Encyclopedia of Korean Culture explains the picture behind the name. A person is compared to a house, and the four parts of the birth time are its pillars.

Each pillar is written with two characters, so a saju chart has eight characters in all. That gives the second name, palja (팔자, 八字), "eight characters". Koreans often say both together, saju palja. The same entry notes that saju palja is also used in everyday speech to mean fate or destiny. The reason is the traditional belief that the eight characters show the fortune a person is born with.

The word saju covers both the chart and the reading of it. To have a reading done is saju-reul boda (사주를 보다), literally "to look at the saju". The table lists the words that come up most often when Koreans talk about it. The meanings given for myeongni and chumyeong follow the encyclopedia's entry on saju.

What are the parts of a saju chart?

A saju chart is four pillars, and each pillar is one Heavenly Stem (cheongan, 천간, 天干) written above one Earthly Branch (jiji, 지지, 地支). There are ten stems and twelve branches. According to the Encyclopedia of Korean Culture, every stem and branch is classed as yin or yang (eumyang, 음양, 陰陽). Each also belongs to one of the five elements (ohaeng, 오행, 五行): Wood, Fire, Earth, Metal and Water. The branches stand for the twelve animals, the months and the hours as well.

Stems and branches pair off in a fixed order into 60 combinations, called yuksipgapja (육십갑자, 六十甲子). Every pillar is one of those 60 pairs. The table shows the four pillars with one worked example: a birth in Seoul on March 15, 1995, at 14:30, as this site's calculator computes it.

The year and month pillars follow the solar terms, not the dates on a wall calendar. The Encyclopedia of Korean Culture states that for saju the new year begins at Ipchun, and that a month changes at the start of its solar term. The traditional tool for finding the pillars is the manseryeok (만세력, 萬歲曆), an almanac that lists the year, month and day pairs across about a hundred years. The saju calculator on this site does the same job from calendar data.

One character matters more than the other seven. The stem of the day pillar is the Day Master (ilgan, 일간, 日干), and it stands for the person the chart belongs to. The encyclopedia describes a saju reading as centered on the day stem. The reader looks at how the other stems and branches combine or clash. The reader also weighs how the five elements produce and control one another, and whether yin and yang are in balance. The entry adds that saju values balance and harmony above all. In the example the Day Master is 乙 (eul), Yin Wood. The Day Master guide describes all ten.

A saju chart is also read through time. The encyclopedia names two moving layers: daeun (대운, 大運), fortune that shifts in ten-year units, and seun (세운, 歲運), fortune that shifts year by year. The step-by-step guide to reading a saju chart takes all of these parts in a fixed order.

Where does saju come from, and how did it reach Korea?

Saju belongs to a system that began in China and is shared across East Asia. The stems and branches, yin and yang and the five elements are all written in Chinese characters. In Mandarin the characters 八字 are read bazi, so the same eight characters are known in Chinese as BaZi. The page on saju and BaZi explains how the two compare.

The method used today is tied to one name. The Academy of Korean Studies publishes a dictionary of the Veritable Records of the Joseon Dynasty (조선왕조실록 전문사전). It has an entry on Xu Ziping (徐子平), whose name is read Seo Japyeong (서자평) in Korean. He was a fortune-reader who lived into the early years of China's Song dynasty. Before the Song dynasty, the entry says, a person's fortune was read mainly from the year pillar. The book that carries his name reads it from the stem of the day pillar instead. The entry calls this a landmark change and says the approach became the mainstream of saju study today. That is why a modern chart starts from the Day Master.

In Korea that book was part of the machinery of government. The same dictionary records that it was an examination text from early to late Joseon (1392–1910). Candidates were tested on it in myeonggwahak (명과학, 命課學), one subject of the eumyanggwa (음양과, 陰陽科). That examination selected officials for the Gwansanggam (관상감, 觀象監), the state office for astronomy and the calendar. The text taught how to foretell a person's inborn fortune from the year, month, day and hour of birth. Its original title is Japyeong Sammyeong Tongbyeon Yeonwon (子平三命通辯淵源). The dictionary says it was compiled by Xu Dasheng (徐大升) of the Southern Song, and that the National Library of Korea holds a copy.

Saju also entered family custom. The Encyclopedia of Korean Culture, in its entry on gunghap, describes the old marriage procedure. The groom's family sent a sajudanja (사주단자, 四柱單子), a paper stating the groom's birth year, month, day and hour. The bride's family had a diviner check it, compatibility included, and replied with a wedding date if the result was good.

These sources do not give a date for the first arrival of four-pillar reading in Korea, so this page does not give one. What they document is narrower. A four-pillar text was a state examination book throughout Joseon, and sending the groom's four pillars to the bride's family was a set step in arranging a marriage.

What do Koreans use saju for today?

Koreans consult saju at turning points: the start of a year, a marriage, a new name, a big decision. The table lists the main occasions and where each is reported.

New Year is the busy season for saju. A 2019 feature in The Korea Herald reported that saju businesses are busiest from December through February, when people want to know what the new year holds.

Marriage is the use with the longest record in these sources. The Encyclopedia of Korean Culture defines gunghap as judging, from the saju of a bride and groom, whether the two suit each other as spouses. Its entry, written in 1995, says the custom has been fading with social change and industrialization, yet some people still decide for or against a marriage on the result. It adds that a poor gunghap has also served as a polite reason to turn down a proposal. The Korea Herald's 2019 feature reports that couples sometimes have gunghap read as something fun to do together. The saju compatibility calculator shows what such a comparison looks at.

Naming rests on the same chart. The encyclopedia's saju entry describes gaeunbeop (개운법, 開運法), ways of turning fortune for the better. Its examples are a good name, a favorable direction and a well-matched gunghap, and it says each is chosen to fit the person's saju.

Saju cafes offer a casual reading. The Korea Herald described in 2019 how street booths and cafe-like saju shops in busy districts invite friends and couples to drop in. In March 2025 it reported that saju cafes in Hongdae and Myeong-dong in Seoul put up signs in English, Japanese and Chinese for visitors from abroad. It also reported that the state-run Seoul Tourism Organization recognized saju cafes as a tourism product in 2024. The same report says fortune-telling is common among Koreans before major life decisions such as marriage, employment or exams.

Not every customer treats saju as fate. The 2019 Korea Herald feature notes that skeptics see a reading as entertainment and counseling, not as a revelation of destiny.

Is saju the same as shamanism or tarot?

No. Saju, sinjeom (신점, 神占, divination through a spirit) and tarot are offered side by side in Korea, but each works from something different.

The Encyclopedia of Korean Culture, in its entry on divination (jeombok, 점복, 占卜), sorts Korean methods into separate kinds. In one kind a spirit is said to descend into the diviner, who then tells fortunes as that spirit, and the entry says this takes a special ability to communicate with spirits. Saju reading (sajujeom, 사주점, 四柱占) is listed in another kind: methods built on yin and yang, the five elements and number, which call for wide knowledge. The entry describes that second kind as having a comparatively systematic theory, in contrast to the chance-based and mystical kinds.

A mudang is a Korean shaman, whose main work is a ritual called gut (굿). Reading saju involves no ritual and no spirit. It needs a birth date and a birth time. The Korea Herald drew the same line in 2019, describing saju shops as more out in the open and more accessible in cost than a mudangjip (무당집), the house of a shaman.

Saju and shamanic divination can meet in practice. The divination entry mentions diviners who cast coins and then match the result against the client's saju. A person who offers both is using two methods, not one.

Tarot is different again. A tarot reading interprets cards drawn during the session, so it has no fixed chart. The Korea Herald's 2025 report lists saju, sinjeom and tarot as three separate kinds of fortune-telling that Koreans turn to.

Saju is also more than the zodiac animal. The animal year, called tti (띠), comes from a single character, the branch of the year pillar. The page on Korean zodiac color animals covers that part of the chart.

Is saju a science?

No. Saju has two layers, and only one of them is exact.

The first layer of saju is calculation. Turning a birth time into eight characters is calendar arithmetic: the solar terms, the cycle of 60 and the time of day. On this site that step is done by a fixed algorithm with no AI model, so the same birth details always give the same chart. The About and method page lists every rule.

The second layer of saju is interpretation, and it is tradition. What a Yin Wood Day Master or a missing element is taken to mean comes from the tradition's own texts and from the practice of readers. None of the sources used for this page reports a scientific test of those meanings. The Encyclopedia of Korean Culture files saju under religion and philosophy. Its divination entry grants that divination looks irrational and unscientific from a modern point of view. In the same passage it argues that divination deserves serious study, because it shaped how Koreans lived and still draws people now.

The Korea Herald's 2019 feature adds a caution of its own. Divination, it says, may be a self-fulfilling prophecy or a confirmation of bias, since people tend to hear what they want to hear.

This site follows the same line. Each description under a chart says what the saju tradition reads into a feature of that chart. Nothing on this site predicts an event, and a chart is not advice about health, money or relationships.