OPEN DATASET · CC BY 4.0
How rare is each main star?
Everyone repeats that some stars are rarer than others. Nobody publishes the numbers. We ran 24,000 birth moments through the same engine that casts charts on this site and counted what came out — here is the whole table, the method, and the raw file.
How it was measured
- · Sample: 24,000 birth moments, drawn with a fixed PRNG seed (20260610) so the whole table can be regenerated exactly.
- · Birth years uniform across 1950–2010; month and day uniform within each month's real length; hour and minute uniform, which keeps all twelve 时辰 uniform after true-solar-time correction.
- · Each sample is cast by the production engine — the same code path as a chart you cast yourself — and its Self-palace main stars and BaZi day master are recorded.
- · Main-star percentages count a multi-star Self palace toward each star it holds, so a two-star palace is counted twice and the fourteen sum to 116.97%. The combination table counts each palace once, toward its exact set, and leaves out the starless palaces — add those 16.15% to the 83.88% below and you are back at 100.
Main star in the Self palace
| Star (rarest first) | Of charts |
|---|---|
| The Iron Wealth武曲 | 8.02% |
| The Minister天相 | 8.13% |
| The Treasury天府 | 8.21% |
| The Blessing天同 | 8.22% |
| The Moon太阴 | 8.22% |
| The Elder天梁 | 8.29% |
| The Sun太阳 | 8.33% |
| The Mystic廉贞 | 8.39% |
| The Wolf贪狼 | 8.42% |
| The Disruptor破军 | 8.46% |
| The Voice巨门 | 8.49% |
| The Emperor紫微 | 8.53% |
| The Strategist天机 | 8.61% |
| The General七杀 | 8.65% |
| The Borrowed-Star Self命无主星 | 16.15% |
Rarest to most common, the fourteen span just 0.63 of a percentage point — the folk claim that one main star is dramatically rarer than the rest does not survive measurement. What is genuinely uncommon is a starless Self palace and the specific two-star pairings below.
Exact star combination
| Self palace holds exactly (rarest first) | Of charts |
|---|---|
| 天府 + 廉贞 | 1.15% |
| 巨门 + 天同 | 1.18% |
| 武曲 + 天相 | 1.22% |
| 紫微 | 1.25% |
| 太阴 + 天同 | 1.29% |
| 武曲 + 七杀 | 1.30% |
| 天梁 + 太阳 | 1.31% |
| 武曲 + 贪狼 | 1.33% |
| 天府 + 武曲 | 1.35% |
| 紫微 + 天相 | 1.35% |
| 武曲 + 破军 | 1.36% |
| 巨门 + 太阳 | 1.37% |
| 紫微 + 破军 | 1.39% |
| 太阳 + 太阴 | 1.40% |
| 天梁 + 天同 | 1.41% |
| 廉贞 + 贪狼 | 1.41% |
| 紫微 + 贪狼 | 1.42% |
| 廉贞 + 破军 | 1.43% |
| 廉贞 + 天相 | 1.44% |
| 天梁 + 天机 | 1.44% |
| 廉贞 + 七杀 | 1.45% |
| 天机 + 太阴 | 1.46% |
| 武曲 | 1.46% |
| 廉贞 | 1.50% |
| 紫微 + 七杀 | 1.50% |
| 巨门 + 天机 | 1.54% |
| 紫微 + 天府 | 1.64% |
| 太阴 | 4.07% |
| 天府 | 4.08% |
| 天梁 | 4.13% |
| 天相 | 4.13% |
| 天机 | 4.17% |
| 贪狼 | 4.26% |
| 太阳 | 4.26% |
| 破军 | 4.29% |
| 天同 | 4.35% |
| 七杀 | 4.39% |
| 巨门 | 4.40% |
BaZi day master (日主)
| Day master (rarest first) | Of charts |
|---|---|
| 辛 Xīn阴金 | 9.74% |
| 庚 Gēng阳金 | 9.79% |
| 丙 Bǐng阳火 | 9.82% |
| 己 Jǐ阴土 | 9.92% |
| 戊 Wù阳土 | 10.00% |
| 乙 Yǐ阴木 | 10.07% |
| 癸 Guǐ阴水 | 10.12% |
| 丁 Dīng阴火 | 10.15% |
| 壬 Rén阳水 | 10.17% |
| 甲 Jiǎ阳木 | 10.22% |
The ten day masters sit close to one tenth each, as the sexagenary day cycle implies. The small spread is a real artefact of the sampled year range, not noise we smoothed away.
Use it
Machine-readable JSON: /api/public/rarity. Licensed CC BY 4.0 — use it anywhere, commercially included, as long as you credit 14 Main Stars with a link to this page. If you want a configuration re-measured with a different year range or sample size, ask and we will run it.
What this dataset is not: it counts how often a configuration occurs in the calendar. It says nothing about the people who hold one. Zi Wei Dou Shu and BaZi are traditional symbolic systems offered for reflection, not verified prediction.