Zodiac Sign Calculator
Enter your birth month and day to instantly find your Western zodiac (star) sign, based on the standard date ranges used in Western astrology.
How the Zodiac Sign formula works
Each of the 12 zodiac signs corresponds to a fixed date range on the calendar, based on the sun's position relative to the zodiac constellations at the time Western astrology's system was established.
Step-by-step calculation
- Take the entered birth month and day.
- Compare it against each sign's standard date range.
- Return the sign whose range includes that date.
Worked example
A birthday of July 15 falls within Cancer's range (June 21 – July 22).
Frequently asked questions
Do zodiac sign date ranges ever vary between sources?
Slightly — different sources sometimes use boundary dates that differ by a day, since the exact date depends on the sun's position, which shifts marginally year to year. This calculator uses commonly cited standard ranges.
Is this the same as a Chinese zodiac sign?
No — the Chinese zodiac uses a completely different 12-year cycle system based on birth year, not a Western sun-sign system based on birth date within a year.