Saju Without a Birth Time: What You Can Still Learn

The fourth pillar of a Saju chart comes from the hour of birth, and plenty of people do not know theirs. The good news is that three of the four pillars, including the most important one, need only the date.

What you keep

The year pillar, including your zodiac animal.
The month pillar, which sets the season of the chart.
The day pillar, including your day master, the character that represents you.

That is six of the eight characters. Your day master, its element, its Yin or Yang polarity, and most compatibility comparisons all come from these.

What you lose

The hour pillar’s two characters. They can tip the element count, for example turning a “missing” element into a present one.
Its traditional meaning. The hour pillar is associated with later life, with children, and with a person’s private ambitions.

How the hour pillar is found

The day is divided into twelve two-hour blocks, each belonging to one earthly branch, starting with the Rat hour from 11 p.m. to 1 a.m. The hour stem is then derived from the day stem. So a birth time accurate to within the right two-hour block is usually enough.

Three cases where time matters more

Born between 11 p.m. and midnight. The Rat hour straddles midnight, and tradition counts it as the start of the next day. This site follows that rule, so an 11:30 p.m. birth takes the next day’s day pillar. Some schools keep the same day instead.
Born on a solar term day. The month, and around early February the year, changes at a specific minute. See why your Saju year might not match your birth year.
Born near a block boundary. Korean clocks run about half an hour ahead of local solar time in Seoul, so some Korean practitioners shift every block by thirty minutes, making the Rat hour 11:30 p.m. to 1:30 a.m. This site uses clock time without that shift. If you were born within half an hour of an odd-numbered hour, your hour pillar depends on the convention.

Why idol charts have three pillars

Idols’ birth dates are public; their birth times are not. Every idol chart on this site therefore shows the year, month and day pillars, with the hour marked unknown, and compatibility is calculated from those three. Your own hour pillar is displayed if you enter a time, but the score compares like with like.

Finding your birth time

Common sources are a birth certificate or hospital record, a baby book, or a parent’s memory of “just after lunch” or “before dawn”, which is often enough to pick the right block. If you cannot find it, leave the time blank on the home page. The result is still yours.

Saju is a cultural tradition, and this site treats it as entertainment. There is no scientific evidence that a birth chart determines personality or predicts the future.