Day pillars

Ren Zi 壬子

Black Rat · A deep sea where great rivers meet

Stage · PeakSeated · RivalKorean · imja ilju
StructureWater Day Master × the Rat (Water)

Yang Water — the open sea. Your day branch carries the same water energy as your Day Master — you are seated on your own root.

Twelve-stagePeak

The summit of the cycle. The most command and the strongest will — which also means the direction it points matters more than usual.

Seated Ten GodRival

A competitive sibling sits in the inner room. Drive and nerve run higher; sharing what is yours comes as the accompanying lesson.

Hidden stems Ren · Companion · 10d Gui · Rival · 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 deep sea where the great rivers gather — among the largest waters in the sixty. The scale of tolerance and strategy is unusual, and, as the sea never shows its depth, few people know the inside.

Is Ren 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 Ren Zi day pillar?

Your day pillar is the stem-branch pair governing the day you were born — Ren Zi (壬子) 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 Ren Zi day pillar like?

Black Rat — the image traditionally attached to it is "A deep sea where great rivers meet". Your Day Master 壬 (Yang Water — the open sea) sits on 子, the Rat, which carries Water. In the twelve-stage cycle that position reads as Peak, and the seated Ten God is Rival.

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. 壬子 is romanised Ren Zi from Mandarin and imja 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.