Do I need my birth time?

No. The year, month, and day pillars — and your Day Master — only need the date. The hour pillar adds a fourth pillar if you know it; if you don't, the chart is still read on three, which is how most readers work when the hour is unknown.

My birthday is on the lunar calendar. Which date do I enter?

Enter the Western (solar) calendar date you were actually born on. Saju is calculated from the solar date and the solar terms, not from the lunar calendar — so you don't need to convert anything.

I was born in January. Why is my year pillar last year's?

Because the saju year starts at ipchun, around February 4th, not on January 1st. A birthday before that point belongs to the previous year's pillar. This is also why the Korean zodiac animal can differ from what a Western 'Chinese zodiac' chart tells you.

Is this the same as the Chinese zodiac?

The zodiac animal is one character of one pillar — the year branch. A saju chart has eight characters across four pillars, so the animal is a small part of a much larger picture.

Is the calculator really free?

Yes. The chart, your Day Master, and the short reading are free with no account. A fuller written reading is a paid option you can take or leave afterwards.

Free saju calculator

Free saju calculator: your four pillars chart

Enter your birth date below and you get your saju chart right away: the four pillars, your Day Master (the character that stands for you), and how the five elements are balanced in your chart. No account, no email, nothing to download.

Saju is the Korean name for the East Asian four pillars system — the same calendar-based chart known as bazi in Chinese, and what English speakers often call a Korean birth chart. The calculation is the same; what you get here is the Korean way of reading it, in plain English.

What the saju calculator gives you

Your four pillars — year, month, day, and (if you know it) hour — written as pairs of calendar characters.
Your Day Master: one of ten characters, two for each element, taken from the day you were born. In saju this is the part of the chart that stands for you.
Your five-element balance — how much wood, fire, earth, metal, and water your chart carries, and which one you lean on.
A short reading of what that combination tends to look like in a person. If it lands, the full reading goes deeper; if not, you've lost nothing.

How the calculation works

A saju chart is not a horoscope. It doesn't look at planets. It takes the moment you were born and writes it in the traditional East Asian calendar — a 60-cycle of ten heavenly stems and twelve earthly branches that every year, month, day, and two-hour block moves through. Your chart is simply your birth moment spelled in that notation.

Two details matter for getting it right. First, the year and month pillars follow the solar terms, not January 1st: the saju year begins at ipchun (the start of spring, around February 4th), so a January birthday usually belongs to the previous year's pillar. Second, the day pillar flips at midnight in your local time, which is why we ask for the date as it was where you were born.

The calculator does that conversion for you and checks it against the same tables a Korean reader would use. There's no interpretation step in the chart itself — the characters are the characters. The reading is where a person comes in.

How to read your result

Start with the Day Master. The ten possibilities — the Great Tree, the Vine, the Sun, the Candle, the Mountain, the Garden Soil, the Sword, the Jewel, the Ocean, the Rain — are plain images for the ten stems, and most people recognise themselves in the first two lines. Then look at the element balance: a chart with a lot of one element and almost none of another tends to describe a person with an obvious strength and an obvious blind spot.

The pillars themselves are the layer underneath. The day branch (the second character of your day pillar) sits under your Day Master and colours it: a Great Tree with roots in water reads differently from one standing on dry earth. The full reading walks through all four pillars this way; the free chart shows you the map.

Ready to see your pillars?

Birth date in, four pillars out. Free, no account.

Calculate my chart

Saju calculator vs bazi calculator

If you've searched for a bazi calculator, you're in the right place — the arithmetic is identical. Saju (사주) is the Korean term, bazi (八字) the Chinese one, and both refer to the four pillars of the birth moment. The differences are in reading conventions and vocabulary, not in the chart. This calculator produces the same pillars either way; the reading that follows is written the Korean way, in English.

What a free chart can and can't tell you

A saju chart is a description of tendencies — a way of putting into words the kind of person you tend to be and the kind of year you tend to have. It is not a forecast and it doesn't claim to be. Sajoo treats it as a tool for self-reflection and, honestly, as a very good conversation: the best use of your chart is to read it with someone who knows you and argue about which lines are true.

Sajoo readings are for entertainment and self-reflection only. They are not predictions and not a substitute for professional advice. Intended for adults (18+).

Questions people ask before they calculate

Do I need my birth time?: No. The year, month, and day pillars — and your Day Master — only need the date. The hour pillar adds a fourth pillar if you know it; if you don't, the chart is still read on three, which is how most readers work when the hour is unknown.
My birthday is on the lunar calendar. Which date do I enter?: Enter the Western (solar) calendar date you were actually born on. Saju is calculated from the solar date and the solar terms, not from the lunar calendar — so you don't need to convert anything.
I was born in January. Why is my year pillar last year's?: Because the saju year starts at ipchun, around February 4th, not on January 1st. A birthday before that point belongs to the previous year's pillar. This is also why the Korean zodiac animal can differ from what a Western 'Chinese zodiac' chart tells you.
Is this the same as the Chinese zodiac?: The zodiac animal is one character of one pillar — the year branch. A saju chart has eight characters across four pillars, so the animal is a small part of a much larger picture.
Is the calculator really free?: Yes. The chart, your Day Master, and the short reading are free with no account. A fuller written reading is a paid option you can take or leave afterwards.