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Yi Hai 乙亥 Day Pillar

Yi Hai 乙亥 is number 12 of the sixty. The Day Master is Yi 乙, yin Wood; the branch Hai 亥 is Water, zodiac Pig. Na Yin is Fire on the Mountaintop.

At a glance

Position in the cycle12 / 60
Day Master (stem)
Day branch
Day Master elementyinWood
Branch elementWater
ZodiacPig
Na YinFire on the Mountaintop
Hidden stemsRen 壬, Jia 甲
Void branchesShen 申, You 酉

Hidden stems and their Ten Gods

A branch is more than its surface element. Hai 亥 hides Ren 壬, Jia 甲; read against the Day Master Yi 乙 they give the Ten God relations below. Hidden stems are what element strength is actually judged on — counting only the four visible stems badly understates what the branches carry.

Hidden stemsDay Master elementTen God
Ren 壬WaterDirect Resource
Jia 甲WoodRob Wealth

Next Yi Hai 乙亥 days

Day pillars run on a fixed 60-day cycle independent of month and year. The dates below are derived straight from the day count, so no calendar reform affects them.

Where Yi Hai 乙亥 sits in a chart

The day pillar is the only one read from itself — every Ten God in the year, month and hour pillars is defined relative to the Day Master Yi 乙. Two people born in the same year and month with different day stems therefore have completely different charts. In Yi Hai 乙亥 the Day Master Yi 乙 is yin Wood and sits on Hai 亥, which is Water; the relation between them is branch produces the Day Master. This seat is classically read as the Day Master's immediate environment.

Related pillars

The other five pillars sharing the Day Master Yi 乙, and the other four sharing the branch Hai 亥:

Same Day Master (Yi 乙)

Same branch (Hai 亥)

Sources

  1. lunar-javascript (6tail, MIT) — solar-term instants, 干支 pillars, 大運/流年, 胎元/命宮/身宮 and the almanac tables.
  2. Hong Kong Observatory, Date and Time of the 24 Solar Terms — the reference used to check solar-term instants.
  3. Xieji Bianfang Shu and Sanming Tonghui — classical sources for the Wuhu Dun and Wushu Dun stem rules, hidden stems and the Ten Gods.

Algorithms last checked: 2026-07 · Method and accuracy