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Ding Si 丁巳 Day Pillar

Ding Si 丁巳 is number 54 of the sixty. The Day Master is Ding 丁, yin Fire; the branch Si 巳 is Fire, zodiac Snake. Na Yin is Earth in the Sand.

At a glance

Position in the cycle54 / 60
Day Master (stem)
Day branch
Day Master elementyinFire
Branch elementFire
ZodiacSnake
Na YinEarth in the Sand
Hidden stemsBing 丙, Geng 庚, Wu 戊
Void branchesZi 子, Chou 丑

Hidden stems and their Ten Gods

A branch is more than its surface element. Si 巳 hides Bing 丙, Geng 庚, Wu 戊; read against the Day Master Ding 丁 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
Bing 丙FireRob Wealth
Geng 庚MetalDirect Wealth
Wu 戊EarthHurting Officer

Next Ding Si 丁巳 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 Ding Si 丁巳 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 Ding 丁. Two people born in the same year and month with different day stems therefore have completely different charts. In Ding Si 丁巳 the Day Master Ding 丁 is yin Fire and sits on Si 巳, which is Fire; the relation between them is the same element. This seat is classically read as the Day Master's immediate environment.

Related pillars

The other five pillars sharing the Day Master Ding 丁, and the other four sharing the branch Si 巳:

Same Day Master (Ding 丁)

Same branch (Si 巳)

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