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How accurate is Saju
if you don't know your birth time?

FAQ · 2026.08.22 · 5 min read · Updated 2026.10.03 · Updated 2026-10-10

The time accounts for two of the eight Saju characters

Saju (四柱) literally means four pillars. Your year, month, day and hour of birth each take two characters, for eight in total — which is why it's called Saju palja (the Four Pillars and Eight Characters).

The key point here is that the day pillar is “you.” The Day Master (the upper character of your birth day), the central axis of a Saju reading, comes out accurately even without the time. So even in a Three Pillars reading (三柱) without the time, six characters — 75% — remain intact.

What a Three Pillars reading shows well enough

• Today's rhythm — the daily reading that comes from how the iljin relates to your Day Master has almost nothing to do with the time.
• The broad strokes of your personality — tendencies like whether you lead with drive or tend to adapt to others first in relationships.
• The big flow of Daeun — the rhythm that changes every 10 years starts from the month pillar, so it can be calculated without the time.
• What kind of work you gain strength in — whether you have an edge in work that's about talking things through, organizing, or bringing people together.

If your purpose is preparing for a specific day like an interview, blind date or exam, a Three Pillars reading is enough. What you need that day isn't a map of your whole life but today's weather.

What becomes clearer when you know the time

On the other hand, some areas blur when the hour pillar is empty. To be honest, these are the ones.

• The flow of later life — the hour pillar covers the second half of life, so the margin of estimation here gets wider.
• Readings about children — when the hour-pillar position is empty, the basis becomes weaker.
• The gap between outside and inside — how the side others see differs from the way you are when you're alone.
• Fine-tuning strength and weakness — when judging the balance of the eight characters, missing two can change the verdict. The more borderline the chart, the more a single character in the hour pillar can change the conclusion.

How to find your birth time

It's still on record more often than you'd think. Here they are, from most to least likely.

1. Hospital records

If you were born in a hospital, the time is written to the minute on your birth certificate. If the hospital is still operating, you can request a copy of the medical records. However, once the medical-record retention period has passed, they may no longer exist.

2. Baby record book, maternity record book, vaccination record book

There's a good chance one is somewhere among your parents' things. The time of birth is often written on the first page.

3. Family memories — but ask smartly

Rather than “What time was I born?”, asking about the circumstances is far more accurate.

“Was it light or dark outside?” · “Was it before or after breakfast?” · “Was Dad at work at the time?” · “What was on the news or the radio?”

The hour pillar changes every 2 hours, so narrowing it down this much usually gets you within one or two slots.

4. The community service center usually won't have it

The family relation register often doesn't record the time of birth. It's easy to make a wasted trip, so keep that in mind.

Why you shouldn't guess when you don't know

This is the most important part. The hour pillar changes every 2 hours. 9 a.m. and 11 a.m. are different characters. If a rough guess is off by even one slot, two characters that aren't yours creep into the reading, and the result is worse than leaving the time out altogether.

If you don't have it, reading without it is the accurate choice. Leave it blank and use a Three Pillars reading; once you confirm the time later, add it then, and the reading becomes more precise from that point. The Mutal Unnie app works the same way — you can start without a birth time and add it anytime in the Me tab.