What Is a Zodiac Sign?
Your zodiac sign (also called a star sign or sun sign) is one of the twelve constellations the Sun appears to pass through during the year in Western astrology. Each sign covers a roughly month-long band of dates, so your birthday determines your sign. This calculator uses the standard tropical zodiac date ranges used in most horoscopes.
How to Use This Calculator
Select your birth month from the dropdown and type the day of the month you were born. Click calculate to instantly see your zodiac sign, its astrological symbol, its classical element (Fire, Earth, Air or Water), and the exact date range that sign spans.
The Formula Explained
There is no arithmetic equation — instead the calculator performs a lookup against fixed boundary dates:
$$\text{sign} = \text{lookup}(\text{month}, \text{day})$$For example, Aries runs from March 21 to April 19. The logic checks whether your month/day pair falls within each sign's start and end date and returns the matching sign. Boundaries (cusp days) are assigned to the sign whose range begins on that day, following the conventional dates.
Worked Example
Suppose you were born on July 23. Cancer ends on July 22, so July 23 falls into the next range: Leo (July 23 – August 22). The calculator returns Leo ♌, a Fire sign. A birthday of August 1 would also return Leo, while August 23 would tip over into Virgo.
FAQ
Are the dates always exactly the same each year? The conventional horoscope dates used here are fixed. The true astronomical moment the Sun changes signs can shift by about a day depending on the year, so if you were born right on a cusp, a precise birth-time chart may differ.
What if I'm born on a cusp day? This tool assigns cusp days to the sign whose range starts that day (for example, March 21 is Aries). For exact results on borderline dates, consult a full birth chart that uses your time and place of birth.
Is this Western or Vedic astrology? It uses the Western tropical zodiac, the system behind most newspaper and online horoscopes. Vedic (sidereal) astrology uses different date ranges.
