Day pillars

Jia Zi 甲子

Green Rat · A straight tree raised on cold spring water

Stage · BathingSeated · ResourceKorean · gapja ilju
StructureWood Day Master × the Rat (Water)

Yang Wood — a tall, upright tree. You are seated on the water energy that feeds you — there is something to lean on underfoot.

Twelve-stageBathing

The stage of washing and dressing. Feeling and appeal stand out here — and so does a mind that ripples more than it settles.

Seated Ten GodResource

A mother-like teacher is seated in your inner room. Learning and support are laid under this seat — receiving is familiar, so standing alone becomes the homework.

Hidden stems Ren · Indirect Resource · 10d Gui · Resource · 20d

The stems concealed inside (Rat). A branch is not one single energy — it holds this mixture, in these proportions across a 30-day month.

A tree drinking cold spring water — the mind stays clear and learning comes quickly. But the roots sit in wet ground, so resolve ripples easily; holding a decision long enough is the classic homework of this pillar.

Is Jia Zi actually your day pillar?

The day pillar shifts on solar-term and zi-hour boundaries, so it is not countable by eye. Enter your birth date and the engine computes it in under a minute — free, no account.

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Frequently asked

How do I know if I have the Jia Zi day pillar?

Your day pillar is the stem-branch pair governing the day you were born — Jia Zi (甲子) in this case. It rotates every day through a cycle of sixty, and the boundaries depend on solar terms and the 11pm zi-hour rule, so it is not something you can count by eye. Enter your birth date in our free reading and the engine computes it directly.

What is the Jia Zi day pillar like?

Green Rat — the image traditionally attached to it is "A straight tree raised on cold spring water". Your Day Master 甲 (Yang Wood — a tall, upright tree) sits on 子, the Rat, which carries Water. In the twelve-stage cycle that position reads as Bathing, and the seated Ten God is Resource.

Does my day pillar tell me my whole chart?

No. The day pillar is two characters out of eight — your core axis, not the whole picture. The year, month and hour pillars, the balance of the five elements, and your decade luck all have to be laid on top before a reading means much. Treat a day-pillar page as the doorway, not the room.

Why is it called Jia Zi in Chinese and something else in Korean?

Same sixty-cycle, different reading of the same characters. 甲子 is romanised Jia Zi from Mandarin and gapja from Korean, and Korean saju calls the day pillar ilju (일주). The calculation is identical; the interpretive traditions differ.

Other pillars with the same Day Master ()

Other pillars seated on the Rat ()

See all 60 day pillars ›

The twelve-stage position, seated Ten God and hidden stems are computed by the Ioreum deterministic engine (ruleset ioreum-2026.07). The reading itself is interpretation from the day-pillar tradition, not verified science — we always tell you which part is calculation and which part is tradition.