Short answer
Saju sorts you by your birth date into one of ten birthday types (and sixty day pillars), while MBTI sorts you by your questionnaire answers into one of sixteen types; one is fixed by when you were born, the other can change when your answers do.
The comparison
| Korean saju | Chinese zodiac | Western zodiac | MBTI | |
|---|---|---|---|---|
| What it reads | Your birth year, month, day and hour | Your birth year | Your birth date (sun sign) | Your answers to a questionnaire |
| Number of core types | 10 birthday types, 60 day pillars | 12 animals | 12 signs | 16 types |
| What sets your core type | The day you were born | The year you were born | The month you were born | How you answer |
| Can it change? | No, it is fixed by your birth date | No | No | Yes, if your answers change |
| Built to compare people? | Yes, couple compatibility (gunghap) is a core use | Loosely, animal pairs | Loosely, sign pairs | Not originally |
| Best used for | Self-reflection, relationships, conversation | Fun, tradition | Fun, reflection | Self-reflection, work and teams |
Where they feel similar
Both give you a short label and a long description. Both are popular in Korea: plenty of people put their MBTI in their dating profile and still check gunghap with their mum. And both work best as conversation starters. 'I am an INFJ' and 'I am a Candle' say roughly the same thing at a party: I go deep, please be gentle with your jokes.
Where they differ
MBTI describes how you prefer to think and decide. Saju describes a temperament through images and elements: a Sword is blunt and protective, a Rain is intuitive and gentle. MBTI is about you alone. Saju was built to compare people, which is why it has a whole tradition of compatibility.
MBTI can change if you retake the test on a different week. Your birthday type never changes, which some people find comforting and others find annoying.
Use both
The fun part is the overlap. An ESTJ Sword and an INFP Sword are both direct, but they are direct in very different ways. We wrote one line for every combination on MBTI x saju. Find your birthday type with the free check.
FAQ
Is saju more accurate than MBTI?
Neither predicts behaviour in a scientific sense. MBTI is a self-report questionnaire; saju is a traditional framework. Both are best used for reflection and conversation.
Do Koreans use MBTI or saju?
Both. MBTI is very popular in Korea for everyday chat and dating profiles, while saju and gunghap remain a familiar tradition, especially around relationships and new years.
Can my MBTI and saju type disagree?
Often, and that is the interesting part. Your MBTI shows how you see yourself now; your birthday type offers a different angle. Where they disagree is worth thinking about.