The word saju (사주, 四柱) means “four pillars.” A pillar is made from one Heavenly Stem and one Earthly Branch. Put the four pairs together and you get eight characters, which is why Koreans also use the name palja—literally, “eight characters.”
The four pillars
The pillars correspond to the birth year, month, day and hour. They are not four isolated labels. Practitioners read the relationships among their stems and branches, seasonal context and other derived symbols.
| Pillar | Basic input | Common interpretive emphasis |
|---|---|---|
| Year | Year of birth | Wider environment, ancestry or public context |
| Month | Solar-term month | Seasonal strength, early environment or work context |
| Day | Day of birth | The Day Master and close personal orientation |
| Hour | Two-hour birth period | Private aims, later life or inner expression |
Those interpretive associations vary by school and should not be treated as fixed scientific facts.
Why there are eight characters
Every pillar has two parts: a Heavenly Stem above and an Earthly Branch below. Four pairs make eight written characters. The stems and branches are part of the traditional East Asian calendrical cycle, not the same thing as the twelve-sign Western zodiac.
Day Master and Five Elements
The Heavenly Stem of the day pillar is commonly called the Day Master. It becomes a reference point for interpreting the rest of the chart. Stems and branches are also associated with Wood, Fire, Earth, Metal or Water, together with yin or yang polarity.
A chart is not simply “good” when one element has a large count or “bad” when an element looks scarce. Season, relationships and calculation method matter. A simple element count is useful as a transparent summary, but it is not a complete strength analysis.
Korean Saju and its wider tradition
Saju is the Korean name and cultural expression of the broader Four Pillars tradition found across East Asia. In Korea, it has historically appeared in discussions of marriage matching, personal fortunes and the coming year. Modern readers may instead use it as a structured prompt for reflection.
A chart and a reading are not the same thing
The chart comes from calendar calculation. The reading comes afterward, when someone interprets the relationships shown in that chart. Hello Saju keeps those jobs separate: software calculates the pillars, and the writing system explains the supplied result in ordinary English. It is not allowed to quietly replace the calculated chart with its own version.