Ding Fire Day Master (丁): the Yin Fire stem in BaZi
Last checked · verse from the Di Tian Sui on Chinese Wikisource; tables calculated
丁 (Ding) is the fourth Heavenly Stem, the yin partner of 丙 Bing in fire. The Di Tian Sui opens its verse with "Ding fire is soft and centered, its inner nature bright and clear", and its annotation describes Ding as warm, gentle fire.
Stem
丁 Ding
Element and polarity
Yin Fire
Combines with
壬 Ren (Wood)
Clashes with
癸 Gui
The Ding verse in the Di Tian Sui (滴天髓)
Verse traditionally attributed to Jingtu (京圖), with the annotation attributed to Liu Ji (劉基, Ming dynasty); quoted from Chinese Wikisource. The translation is ours.
丁火柔中，內性昭融，抱乙而考，合壬而忠，旺而不烈，衰而不窮，如有嫡母，可秋可冬。
Ding fire is soft and centered, its inner nature bright and clear. Embracing Yi, it is filial; combining with Ren, it is loyal. Strong, it is not fierce; weak, it does not run out. If it has its true mother, it can last through autumn and winter.
The verse uses human words (kind, loyal, filial) for how the stems act on one another in a chart; it does not describe people.
What the annotation says
Yi is Ding's mother: Ding shelters Yi from Xin, which the annotation calls filial. Ren is Ding's lord: Ding nurtures Wu earth so that it does not bully Ren, and by combining with Ren into wood it keeps Wu from resisting Ren, which it calls loyal. Born in summer, its flame does not become excessive; in autumn or winter, a single Jia keeps it from running out (the annotation's reading of "if it has its true mother").
The annotation opens with 「丁為溫煖之火」 (warm, gentle fire). Summarized in our words from the annotation on the same 天干論 page on Wikisource.
Fire in the Huainanzi (淮南子)
The Huainanzi, 天文訓 chapter, lists each direction with its element, season, planet and animal, and ends with the two stems of its days.
南方，火也……執衡而治夏。其神為熒惑，其獸朱鳥，其音徵，其日丙丁。
Direction: South · Season: Summer · Planet: Mars (熒惑) · Animal: Vermilion Bird (朱鳥) · Note: zhi (徵)
Ten Gods for a Ding Fire Day Master
What each of the ten stems is called, seen from this Day Master.
| Stem | Element | Ten God | Chinese |
|---|---|---|---|
| 甲 Jia | Yang Wood | Direct Resource | 正印 Zheng Yin |
| 乙 Yi | Yin Wood | Indirect Resource | 偏印 Pian Yin |
| 丙 Bing | Yang Fire | Rob Wealth | 劫财 Jie Cai |
| 丁 Ding | Yin Fire | Friend | 比肩 Bi Jian |
| 戊 Wu | Yang Earth | Hurting Officer | 伤官 Shang Guan |
| 己 Ji | Yin Earth | Eating God | 食神 Shi Shen |
| 庚 Geng | Yang Metal | Direct Wealth | 正财 Zheng Cai |
| 辛 Xin | Yin Metal | Indirect Wealth | 偏财 Pian Cai |
| 壬 Ren | Yang Water | Direct Officer | 正官 Zheng Guan |
| 癸 Gui | Yin Water | Seven Killings | 七杀 Qi Sha |
Twelve stages of Ding (长生十二宫)
A yin stem runs backward through the branches from its Growth stage.
| Branch | Animal | Stage |
|---|---|---|
| 酉 You | Rooster | 长生 Growth |
| 申 Shen | Monkey | 沐浴 Bath |
| 未 Wei | Goat | 冠带 Cap and Belt |
| 午 Wu | Horse | 临官 Taking Office |
| 巳 Si | Snake | 帝旺 Prosperity |
| 辰 Chen | Dragon | 衰 Decline |
| 卯 Mao | Rabbit | 病 Sickness |
| 寅 Yin | Tiger | 死 Death |
| 丑 Chou | Ox | 墓 Tomb |
| 子 Zi | Rat | 绝 Extinction |
| 亥 Hai | Pig | 胎 Conception |
| 戌 Xu | Dog | 养 Nurture |
The six Ding day pillars
Ding pairs only with the yin branches, so it appears in six of the sixty pillars.
| Pillar | No. in the cycle | Na Yin | Void branches |
|---|---|---|---|
| 丁卯 Ding Mao | 4 | 炉中火 Furnace Fire | 戌亥 |
| 丁丑 Ding Chou | 14 | 涧下水 Stream Water | 申酉 |
| 丁亥 Ding Hai | 24 | 屋上土 Rooftop Earth | 午未 |
| 丁酉 Ding You | 34 | 山下火 Foot of the Mountain Fire | 辰巳 |
| 丁未 Ding Wei | 44 | 天河水 Heavenly River Water | 寅卯 |
| 丁巳 Ding Si | 54 | 沙中土 Sand Earth | 子丑 |
Ding is also a hidden stem in 午 Wu (as the main stem), 未 Wei and 戌 Xu.
Next Ding days
China Standard Time dates; one day in every ten.
- Oct 20, 2026 · 丁卯
- Oct 30, 2026 · 丁丑
- Nov 9, 2026 · 丁亥
- Nov 19, 2026 · 丁酉
- Nov 29, 2026 · 丁未
- Dec 9, 2026 · 丁巳
FAQ
How do I find out if my Day Master is Ding Fire?
Your Day Master is the stem of your day pillar. Enter your birth date, time and time zone in the BaZi calculator; if the day pillar starts with 丁, your Day Master is Ding.
What is a Ding Fire Day Master?
A BaZi chart whose day pillar has 丁 (Ding) as its stem. Ding is the fourth of the ten Heavenly Stems, the yin stem of fire. The Di Tian Sui annotation describes it as warm, gentle fire (丁為溫煖之火).
What is the difference between Ding and Bing?
Both are fire. Ding (丁) is the yin stem and Bing (丙) the yang one. The Di Tian Sui annotation describes Ding as warm, gentle fire and Bing as blazing, burning fire. Ding combines with Ren and Bing with Xin.
Which stem combines with Ding, and which clashes with it?
Ding combines with 壬 Ren (the 丁壬 combination, associated with Wood). It clashes with 癸 Gui.
How common is a Ding Day Master?
The day stems repeat every ten days without a break, so exactly one day in ten is a Ding day. The next ones are Oct 20, 2026, Oct 30, 2026, Nov 9, 2026 (China Standard Time dates).
Where does Ding sit in the twelve stages?
In the usual twelve-stage table, Ding has its Chang Sheng (Growth) in 酉 You and its Di Wang (Prosperity) in 巳 Si; as a yin stem it moves backward through the branches.
Other Day Masters
Sources: 滴天髓 (Di Tian Sui), 天干論, on Chinese Wikisource; 淮南子 (Huainanzi), 天文訓, on Chinese Wikisource; Ten God names as in 淵海子平 (Yuan Hai Zi Ping) on Chinese Wikisource. This page describes the traditional system and quotes classical texts; it is not a character reading, a prediction or advice. Terms are given in simplified characters; quotations keep the script of their source. Day pillars: how they are calculated and checked.