Born on May 21
May 21: Gemini Zodiac & Famous People
The zodiac sign for May 21 is Gemini. Famous people born on May 21 include Mr. T, Rinka — 2 notable figures in all, plus this day’s birthstone, birth flower and birthday rarity.
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How many people share the May 21 birthday?
~930 thousand in the U.S., ~22 million worldwide
※ Rough estimate assuming birthdays are evenly distributed (published population figures).
The May 21 birthday profile
Zodiac
Gemini
Birthstone
Emerald
Birth flower
Lily of the Valley
Birth color
Jade
Rarity
#143/366
Weekday
Which day?
💎 Emerald (Luck, Happiness & Hope) · 🌸 Lily of the Valley (Return of Happiness & Purity)
Gemini traits
General traits of the sign May 21 falls under (5/21–6/21) — not a per-day personality or fortune.
Element
Air
Modality
Mutable
Ruling planet
Mercury
Curious, quick-witted and versatile, juggling many interests with ease.
Associated strengths: Adaptable, Witty, Sociable, Curious
May 21's decan: 1st decan (0°–10°, ~May 21–May 30) — sub-ruler Mercury (Gemini)
Each sign splits into three 10° decans; the 1st is the sign itself, the 2nd and 3rd are sub-ruled by the same-element signs (a traditional rule; the boundary shifts ±1 day by year).
※ Traditional Western astrology attributes — for cultural interest, not a scientific claim.
🎂 Born on May 21?
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