almanarkASTRONOMICAL CALENDAR
English·繁體中文

Geng Zi 庚子 Day Pillar

Geng Zi 庚子 is number 37 of the sixty. The Day Master is Geng 庚, yang Metal; the branch Zi 子 is Water, zodiac Rat. Na Yin is Earth on the Wall.

At a glance

Position in the cycle37 / 60
Day Master (stem)
Day branch
Day Master elementyangMetal
Branch elementWater
ZodiacRat
Na YinEarth on the Wall
Hidden stemsGui 癸
Void branchesChen 辰, Si 巳

Hidden stems and their Ten Gods

A branch is more than its surface element. Zi 子 hides Gui 癸; 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
Gui 癸WaterHurting Officer

Next Geng Zi 庚子 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 Zi 庚子 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 Zi 庚子 the Day Master Geng 庚 is yang Metal and sits on Zi 子, which is Water; the relation between them is Day Master produces the branch. 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 Zi 子:

Same Day Master (Geng 庚)

Same branch (Zi 子)

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