Saju

One moment of birth,
read as four pillars.

What this is

Your birthday, the time of day, and where you were born.

Saju is Korea's birth chart. A star sign uses one thing about your birth — the date. Saju uses four: the year, the month, the day and the hour. Each becomes a pair of symbols, which is where the name comes from: four pillars.

Those eight symbols carry a mix of five elements — wood, fire, earth, metal, water. What matters isn't which ones you have. It's the balance: what you've got too much of, and what's missing entirely. That imbalance is the part that describes your actual life.

Koreans use this the way the West uses personality tests. It's about a thousand years old and considerably more specific.

Don't know your birth time? Fine — tick the box and we'll read three pillars instead of four.

Full name optional Sex at birth Used only to set the direction of your ten-year cycles.

Birth date

Time of birth

AM PM

I don't know my birth time Midnight is 12 AM. Noon is 12 PM. Get it as close as you can — a few minutes rarely changes anything, but near midnight or right on a two-hour boundary, a few minutes can change your whole chart. We correct for your birthplace's real solar time, so those boundaries usually aren't where the clock says they are.

Place of birth Your longitude changes the chart. An Atlanta birth runs 38 minutes behind its own clock in winter — and 98 minutes behind in summer.

No account. No card. Takes about four seconds.

Why this one is different

Real solar time

Most free calculators feed your wall clock straight in. We convert to true solar time at your birth longitude — and apply the daylight saving rules that were actually in force that year.

Correct year boundary

The Four Pillars year turns at Lichun in early February, not January 1 — at an exact instant. Born near it in the Americas? Most tools get your year pillar wrong. This one doesn't.

Written for you, not translated