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Geng Wu 庚午 Day Pillar

Geng Wu 庚午 is number 7 of the sixty. The Day Master is Geng 庚, yang Metal; the branch Wu 午 is Fire, zodiac Horse. Na Yin is Earth by the Roadside.

At a glance

Position in the cycle7 / 60
Day Master (stem)
Day branch
Day Master elementyangMetal
Branch elementFire
ZodiacHorse
Na YinEarth by the Roadside
Hidden stemsDing 丁, Ji 己
Void branchesXu 戌, Hai 亥

Hidden stems and their Ten Gods

A branch is more than its surface element. Wu 午 hides Ding 丁, Ji 己; read against the Day Master Geng 庚 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
Ding 丁FireDirect Officer
Ji 己EarthDirect Resource

Next Geng Wu 庚午 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 Geng Wu 庚午 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 Geng 庚. Two people born in the same year and month with different day stems therefore have completely different charts. In Geng Wu 庚午 the Day Master Geng 庚 is yang Metal and sits on Wu 午, which is Fire; the relation between them is branch controls 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 Geng 庚, and the other four sharing the branch Wu 午:

Same Day Master (Geng 庚)

Same branch (Wu 午)

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