Day Master Calculator

Your Day Master is the core of a Korean Four Pillars (Saju) chart — the element of the day you were born, and the closest thing Saju has to a sun sign. It takes one date to find. No birth time needed.

Year

Month

Day

Birth time (optional)

Country of birth (optional — sharpens the hour)

What is a Day Master?

In Korean Saju — and its Chinese cousin, BaZi — your birth moment is written as four pillars: year, month, day, and hour. The Day Master is the heavenly stem of your day pillar, and the whole chart is read relative to it. Ten Day Masters exist: five elements (Wood, Fire, Earth, Metal, Water), each in a yang or yin form.

Why don't I need my birth time?

The day pillar changes at the day boundary, not by the hour — so your date alone pins it down. Your birth time adds the hour pillar (two more characters), which sharpens the element balance and unlocks a fuller reading. Curious how the calendar math works? Read how a Saju chart is calculated.