If you were born on March 21, your zodiac sign is Aries. The Sun occupies approximately 2° Aries on this date, placing you in the 1st decan ruled by Mars.
Cusp Analysis
Born on March 21, you sit at the edge of the Pisces-Aries cusp (The Cusp of Rebirth). While your Sun is technically in Aries, the influence of the neighboring sign is already prominent. The cusp spans March 18–22.
Learn more about The Cusp of Rebirth →Best Compatibility for March 21
♈ & ♌
Aries & Leo
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♈ & ♐
Aries & Sagittarius
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♈ & ♒
Aries & Aquarius
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Fellow fire signs Leo and Sagittarius match Aries' passion and appetite for adventure without trying to tame them. Aquarius provides intellectual stimulation and shared independence that keeps the spark alive long-term.
Your Decan: 1st Decan of Aries
Each zodiac sign spans 30° of the ecliptic, divided into three decans of 10° each. Born on March 21 at approximately 2° Aries, you fall in the 1st decan (0°–10° Aries).
As a 1st decan Aries, your sub-ruler is also Mars — the same planet that rules Aries overall. This double Mars influence concentrates and amplifies the core Aries traits, making you a particularly pure expression of this sign's energy.
Lucky Numbers, Colors & Symbols
Lucky Numbers
3, 12, 21, 30
Lucky Color
Red
Lucky Day
Tuesday
Birthstone
Aquamarine
Birth Flower
Daffodil
Healing Crystal
Carnelian
Sabian Symbol
"A comedian entertaining a group of friends"
Numerology
3
Season
Spring
Element
Fire
Modality
Cardinal
Historical Events on March 21
- • 1556: Archbishop Thomas Cranmer is burned at the stake for heresy
- • 1804: Code Napoléon (French civil code) is adopted
- • 1965: Martin Luther King Jr. leads the third Selma-to-Montgomery march
- • 2006: Twitter co-founder Jack Dorsey sends the first tweet
Frequently Asked Questions
Is March 21 Pisces or Aries?
March 21 falls on the Pisces-Aries cusp. The Sun typically moves from Pisces into Aries around this date each year, so your exact sign depends on the year and time of birth. Swiss Ephemeris calculations show the Sun enters Aries at varying times. Based on the standard date, your Sun sign is Aries, but you'll likely feel both signs' influence.
What are the personality traits of someone born on March 21?
People born on March 21 are Aries natives with Fire element energy and Cardinal modality. The 1st decan sub-ruled by Mars adds a distinctive layer to the core Aries personality, making these individuals unique among their sign.
Who is March 21 most compatible with?
March 21 Aries natives are most compatible with signs that share the Fire element (trine aspect) or complementary elements. Check the compatibility section above for specific sign matches and the best romantic dates.
What is the birthstone for March 21?
The traditional birthstone for people born on March 21 is Aquamarine. The decan-specific healing crystal is Carnelian, which resonates with the Mars-influenced energy of the 1st decan of Aries.
What decan is March 21?
March 21 falls in the 1st decan of Aries (approximately 2° Aries). This decan is sub-ruled by Mars, which adds concentrated energy to the core Aries traits.
What famous people were born on March 21?
While our celebrity database is still growing, all people born on March 21 share the Aries Sun sign at approximately 2° with Mars decan influence.
What is the lucky number for someone born on March 21?
The numerology root for March 21 is 3. Lucky numbers include 3, 12, 21, 30. The lucky day is Tuesday (ruled by Mars), and the lucky color is Red.
What element is March 21?
March 21 belongs to the Fire element through Aries. Fire signs are known for intuition, emotional depth, and empathy.
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