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Zodiac Sign

General

Sun Sign

The one of 12 astrological signs assigned by the position of the Sun on your birth date, determined by fixed Western tropical calendar date ranges (e.g., Aries: Mar 21 – Apr 19).

Definition

A zodiac sign — also called a sun sign — is one of 12 astrological signs assigned based on where the Sun was positioned along the ecliptic (from Earth's point of view) on a person's date of birth. In the Western tropical system used across the US, UK, and most of the world, each sign corresponds to a fixed range of calendar dates that does not shift from year to year.

Every sign carries an associated element (Fire, Earth, Air, or Water), a modality (Cardinal, Fixed, or Mutable), and a ruling planet, all of which feed into the personality traits traditionally linked to that sign. Because the sun sign only requires a birth date — not a birth time or location — it is the most commonly used and most accessible piece of astrological information.

Formula

Determining a zodiac sign is a direct date-range lookup rather than a calculation:

Sign Date Range Element Ruling Planet
Capricorn Dec 22 – Jan 19 Earth Saturn
Aquarius Jan 20 – Feb 18 Air Uranus
Pisces Feb 19 – Mar 20 Water Neptune
Aries Mar 21 – Apr 19 Fire Mars
Taurus Apr 20 – May 20 Earth Venus
Gemini May 21 – Jun 20 Air Mercury
Cancer Jun 21 – Jul 22 Water Moon
Leo Jul 23 – Aug 22 Fire Sun
Virgo Aug 23 – Sep 22 Earth Mercury
Libra Sep 23 – Oct 22 Air Venus
Scorpio Oct 23 – Nov 21 Water Pluto
Sagittarius Nov 22 – Dec 21 Fire Jupiter

The birth month and day are matched against these ranges to find the corresponding sign — no birth year, time, or location is needed for a sun sign.

Worked Example

Priya was born on August 15. Matching against the table above, August 15 falls between Jul 23 and Aug 22, so her zodiac sign is Leo — a Fire sign ruled by the Sun.

Dev was born on March 19, just two days before the Aries range begins (Mar 21). His date falls within Feb 19 – Mar 20, making his zodiac sign Pisces, a Water sign ruled by Neptune, even though his birthday is close to the Aries boundary.

Use the Zodiac Sign Calculator to instantly find your sign from your date of birth, the Zodiac Element Calculator to see your element and modality, and the Zodiac Personality Calculator for a full traits breakdown.

Key Things to Know

  • Date ranges are fixed, not year-dependent: Unlike leap-year rules or lunar calendars, Western zodiac date ranges are the same every single year — Aries always runs Mar 21–Apr 19 regardless of the birth year.
  • Births near a boundary may be "on a cusp": If a birth date falls within a few days of a sign's start or end date, it's sometimes described as being on the cusp of two signs — see Zodiac Cusp for the exact definition used on this platform.
  • The sun sign is only one layer of astrology: Full birth-chart astrology also considers rising sign and moon sign, which require birth time and location — the sun sign captures only the Sun's position and is the simplest entry point.
  • Elements group signs into four temperaments: Fire, Earth, Air, and Water signs are traditionally seen as sharing compatible energy, which is why compatibility discussions often start by comparing elements rather than individual signs.
  • Western and Chinese zodiac signs are unrelated systems: A Western sun sign is based on birth date within a year; a Chinese zodiac animal is based on birth year within a 12-year cycle. The two do not combine into a single calculation and should be treated separately.

Related Calculators

Zodiac Sign Calculator →Find your Western zodiac sun sign instantly from your date of birth. Get your symbol, date range, element, and ruling planet in one click.
Zodiac Cusp Calculator →Find out if your birth date falls on a zodiac cusp. Enter your date of birth to see your primary sign, adjacent sign, and cusp name instantly.
Zodiac Personality Calculator →Explore the personality traits, strengths, weaknesses, and best matches for any zodiac sign. Pick a sign and get an instant astrology personality profile.
Zodiac Element Calculator →Find the element, modality, and ruling planet of any zodiac sign instantly. See whether a sign is Fire, Earth, Air, or Water and what that means.

Related Terms

Zodiac CuspAstrological CuspChinese ZodiacSheng Xiao (12 Earthly Branch Animals)

Frequently Asked Questions

The 12 Western zodiac signs, in calendar order, are: Capricorn (Dec 22 – Jan 19), Aquarius (Jan 20 – Feb 18), Pisces (Feb 19 – Mar 20), Aries (Mar 21 – Apr 19), Taurus (Apr 20 – May 20), Gemini (May 21 – Jun 20), Cancer (Jun 21 – Jul 22), Leo (Jul 23 – Aug 22), Virgo (Aug 23 – Sep 22), Libra (Sep 23 – Oct 22), Scorpio (Oct 23 – Nov 21), and Sagittarius (Nov 22 – Dec 21). Each range is fixed to the tropical calendar and does not shift year to year. A person's zodiac sign is determined purely by matching their birth day and month to the range it falls within.
Yes — in everyday use, 'zodiac sign' and 'sun sign' refer to the same thing: the sign the Sun was passing through (from Earth's perspective) on the day you were born. Astrology also uses 'rising sign' (based on birth time and location) and 'moon sign' (based on the Moon's position), but these require more detailed birth data. The sun sign is the simplest and most widely used, since it only needs a birth date.
The 12 signs are grouped into four elements of three signs each: Fire (Aries, Leo, Sagittarius) — passionate and bold; Earth (Taurus, Virgo, Capricorn) — grounded and practical; Air (Gemini, Libra, Aquarius) — curious and communicative; and Water (Cancer, Scorpio, Pisces) — emotional and intuitive. Signs sharing an element are traditionally considered to have compatible temperaments, since they approach life through the same underlying energy.
Yes. In traditional astrology, each sign is associated with a ruling planet believed to shape its core traits: Aries–Mars, Taurus–Venus, Gemini–Mercury, Cancer–Moon, Leo–Sun, Virgo–Mercury, Libra–Venus, Scorpio–Pluto, Sagittarius–Jupiter, Capricorn–Saturn, Aquarius–Uranus, and Pisces–Neptune. The ruling planet is often cited alongside the element and modality (cardinal, fixed, or mutable) to build a fuller personality profile for the sign.
No, they are entirely different systems. The Western zodiac sign (sun sign) is based on the Sun's position within a calendar year and changes roughly every month. The Chinese zodiac assigns one of 12 animals to an entire birth year rather than a birth date, cycling every 12 years. Someone can have, for example, a Western sign of Leo and a Chinese zodiac animal of Dragon at the same time — the two systems are calculated independently and are not meant to be combined mathematically.