What the zodiac is
The zodiac is a belt of twelve constellations along the ecliptic — the Sun's apparent yearly path through the sky — divided by astrologers more than two thousand years ago into twelve equal signs of 30 degrees each. Your sun sign, the one this calculator finds, is simply the sign the Sun was passing through on your birthday: no birth time, birthplace or chart is needed, which is why it is the sign everyone knows and the one newspaper horoscopes are written for. Enter your date of birth and the answer, its element, its traditional keywords and a short portrait appear instantly, with the full twelve-sign table below so you can look up anyone else's just as fast.
The four elements
The twelve signs are grouped into four elements, three signs each, and the element is traditionally said to set the sign's basic temperament. Fire signs (Aries, Leo, Sagittarius) are linked with energy, enthusiasm and acting first. Earth signs (Taurus, Virgo, Capricorn) with practicality, patience and building real things. Air signs (Gemini, Libra, Aquarius) with ideas, conversation and connection. Water signs (Cancer, Scorpio, Pisces) with feeling, intuition and memory. Whether or not you credit any of it, the element system is the grammar the whole tradition is written in — most horoscope writing is element first, sign second.
Cusps, honestly
Born on the day a sign changes? You will find sources disagreeing by a day, and they are not all being careless: the Sun crosses from one sign to the next at a specific moment that falls on a different calendar day in different years, so a birthday on a boundary — a "cusp" — genuinely depends on the year (and, at the edges, the time) of birth. This page uses the most commonly published tropical date ranges and says so openly; treat a boundary birthday as belonging to whichever neighbouring sign you prefer, or look up an ephemeris for your exact birth year if you want the astronomical answer.
Worked example
Born on October 12 — the default birthday here, October 12, 1990 — and the date sits inside September 23 – October 22, so the sign is Libra, an Air sign with the keywords fair, sociable and harmony-seeking. A birthday five days later is still Libra; a birthday on October 24 would be Scorpio.
How to use this calculator
- Enter your date of birth.
- Read your sign in the headline panel.
- Check the breakdown for your element, date range, keywords and portrait.
- Look through the twelve-sign table below to find friends' and family's signs.
- If your birthday is on a boundary day, read the cusp note before declaring a winner.
Tropical or sidereal? Two zodiacs
There are two living zodiac systems, and they no longer agree. The tropical zodiac, used in Western astrology and on this page, is anchored to the seasons: Aries begins at the March equinox, whatever stars are behind the Sun. The sidereal zodiac, used in Vedic (Indian) astrology, is anchored to the constellations themselves. Because Earth's axis slowly wobbles — the precession of the equinoxes, about one degree every 72 years — the two have drifted roughly 24 degrees apart since they were aligned in antiquity, so a sidereal chart often places the Sun one sign earlier than a tropical one. Neither is a mistake; they are different reference frames, and confusing them is the source of the famous "NASA changed your sign" headlines, which simply rediscover the drift every few years.
An honest framing
CalcViso's position is the one printed in the note under the calculator: the zodiac is a rich, old tradition and a genuinely fun way to talk about personality — and it is entertainment, not science. Controlled tests have not found sun signs predicting personality or life outcomes beyond chance, and the portraits here are written as the tradition describes the signs, not as findings about you. Enjoy the table, argue about the cusps, and let the signs be what they have been for most of their long history: a shared language for describing people, best held lightly.