To find your zodiac sign, match your birth date on the regular (Gregorian) calendar to the 12 date ranges below. Each sign covers a fixed stretch of the year. Someone born on April 5 is an Aries, and someone born on November 20 is a Scorpio. Western astrology follows the solar calendar, not the lunar one, so use the date printed on the birth certificate. This guide gives the full chart with exact dates, plus how to handle a birthday that falls right on the edge between two signs.

What Is a Zodiac Sign by Birth Date?

Your zodiac sign is the position of the Sun along the ecliptic at the moment you were born. The ecliptic is divided into 12 equal parts, each named after a constellation and lasting about 30 days.

The sign most people mean is the "Sun sign." It is the most familiar sign in popular astrology. You can find it from your birth date alone, without knowing your birth time or birthplace.

A common mix-up is thinking you must use a lunar calendar date. Western astrology always counts by the solar calendar, because it follows the apparent movement of the Sun through the year.

In short: your zodiac sign (Sun sign) is where the Sun stood when you were born. It comes from your solar calendar birth date, not a lunar date.

Zodiac Sign Chart by Birth Date

Here is the full chart of the 12 signs with their solar calendar date ranges. Find the range that contains your birthday, and the matching row is your sign.

Zodiac sign	Dates	Element
Aries	March 21 to April 19	Fire
Taurus	April 20 to May 20	Earth
Gemini	May 21 to June 20	Air
Cancer	June 21 to July 22	Water
Leo	July 23 to August 22	Fire
Virgo	August 23 to September 22	Earth
Libra	September 23 to October 22	Air
Scorpio	October 23 to November 21	Water
Sagittarius	November 22 to December 21	Fire
Capricorn	December 22 to January 19	Earth
Aquarius	January 20 to February 18	Air
Pisces	February 19 to March 20	Water

Capricorn runs across two calendar years, from December 22 of one year to January 19 of the next. If you were born in late December or early January, this is the sign to check.

In short: the 12 signs are spread evenly through the year, about a month each. Look up your solar calendar birthday in the chart to find your sign.

How Do You Check a Cusp Birthday?

The dates above can shift by a day depending on the year. A calendar year is not exactly 365 days, and leap years add another adjustment, so the moment the Sun changes signs may fall on the 19th, 20th or 21st depending on the year.

That is why someone born on the very first or last day of a sign is called a cusp birth. For these birthdays, the general chart is not enough to be sure.

To know for certain, you need three details: the day, the time and the year of birth. Someone born on April 20 may be an Aries, while another person with the same birthday in a different year may be a Taurus, depending on the exact time the Sun changed signs that year.

The table below lists the cusp date ranges worth watching:

Cusp range	The two neighboring signs
April 18 to 21	Aries / Taurus
May 19 to 21	Taurus / Gemini
June 19 to 21	Gemini / Cancer
July 21 to 23	Cancer / Leo
August 21 to 23	Leo / Virgo
September 21 to 23	Virgo / Libra
October 21 to 23	Libra / Scorpio
November 20 to 23	Scorpio / Sagittarius
December 20 to 23	Sagittarius / Capricorn
January 18 to 21	Capricorn / Aquarius
February 17 to 20	Aquarius / Pisces
March 18 to 21	Pisces / Aries

In short: the sign changeover can move by a day from year to year. If you were born right at a boundary, check your exact time and year instead of trusting the general chart completely.

You can also see your own chart and more on HOROS.

Why Does Western Astrology Use the Solar Calendar?

Many newcomers ask why Chinese systems such as Zi Wei Dou Shu use the lunar calendar while zodiac signs use the solar one. The answer is that the two systems watch two different things in the sky.

Western astrology is built around the Sun. The solar calendar is designed to follow the Sun's yearly cycle, so a given solar date matches almost the same Sun position year after year. That is why your sign stays steady for a given solar birthday.

A quick comparison makes it easier to picture:

Point	Zodiac sign (Western)	Note
Calendar used	Solar calendar	Follows the Sun's cycle
What fixes the sign	Birth date	Birth time only matters on a cusp
How it is divided	12 signs, about 30 days each	Spread evenly through the year
What is observed	The Sun's position on the ecliptic	Not linked to the Moon's cycle

This is only a difference in method and tradition, not a case of one system being more correct than the other. Each has its own logic and its own value as a reference.

In short: Western astrology uses the solar calendar because it tracks the Sun's position, which keeps your sign steady by solar birth date from year to year.

How to Use Your Sign in Practice

Knowing your Sun sign is a starting point, not your whole star map. It shows a prominent leaning in your personality and how you tend to present yourself to others.

When you read about your sign, keep a reference-only mindset. Every sign has strengths and a few things worth working on, and no sign is "good" or "bad" compared with another. The aim is to understand yourself better and choose how to respond with more intention.

One practical point to remember: two people with the same sign can have very different personalities, and that is normal. The Sun sign is only one slice. The Moon's position, the Ascendant and the other planets are what complete the picture.

A simple way to use the chart:

What you want to do	A simple way to do it
Find your sign	Match your solar calendar birthday to the 12-sign chart
Born right at a boundary	Check your birth time and year as well
Go deeper	Look at your Moon sign and Ascendant
Read interpretations	Keep a reference mindset and focus on what to work on

In short: the Sun sign is a good first slice for understanding your tendencies. Read it as a reference, and look at other factors if you want the fuller picture.

Wrapping Up

Finding your zodiac sign is simple once you know a few principles:

• Always use your solar calendar birth date, not a lunar date.
• Match your birthday to the 12-sign chart to find your Sun sign.
• If you were born close to a boundary, check your birth time and year to be sure.
• The changeover date can shift by a day depending on the year, so a general chart is only an approximate reference.
• Your Sun sign is a starting slice. Read it to understand yourself, not to judge your fate.

If you want to go further than a basic chart and see a personalized reading based on your exact birth date and time, you can look at the personal report from HOROS. Understanding yourself better is often the first step toward more active choices ahead.