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Sun Sign Calculator
Find your sun sign in both systems. This free sun sign calculator shows your Western (tropical) sign from the familiar date ranges and your Vedic (sidereal) sign from the Sun's real position against the stars — and explains the roughly 24-degree ayanamsa gap that makes the two answers differ.
| Western (tropical) sign | — |
| Vedic (sidereal) sign | — |
| Sun sidereal longitude | — |
| Ayanamsa applied | — |
The two systems differ by the ayanamsa — about 24 degrees — so your Vedic sign is often one sign earlier than your Western sign.
How to use this calculator
- Enter your birth date — no birth time is needed for a Sun sign.
- Use the two tabs to switch the headline result between the Western and Vedic systems.
- Press Find my sun sign if the result has not already updated.
- Compare both signs in the table: the Western sign from the familiar date ranges, and the Vedic sign from the Sun's real sidereal position.
How the two sun signs work
Your Western sun sign comes from a fixed table of date ranges: the tropical zodiac is anchored to the seasons, with 0 degrees of Aries at the March equinox, and the Sun is taken to move through the twelve signs in step with the calendar. It is the sign of newspaper horoscopes, and this tool's Western tab simply looks your date up in that table.
Your Vedic sun sign is measured against the fixed stars instead. Because the Earth's axis wobbles slowly (precession), the tropical and sidereal zodiacs have drifted apart by the ayanamsa — about 24 degrees today. The Vedic tab therefore takes the Sun's actual tropical longitude at noon IST on your birth date, subtracts the Lahiri ayanamsa, and reads the sign from the sidereal longitude:
The practical effect: the Sun spends roughly 14 April to 14 May in sidereal Aries (Mesha), a month later than the Western Aries season, so most people find their Vedic sun sign is the one before their Western sign. Note that in Vedic astrology the more personal sign is actually the Moon sign (rashi) — the Sun sign is shown here because so many people ask for it, and our Rashi Calculator will give you the Moon sign from your birth time.
| Western sign | Date range (tropical) |
|---|---|
| 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 |
| Sagittarius ♐ | Nov 22 – Dec 21 |
| Capricorn ♑ | Dec 22 – Jan 19 |
| Aquarius ♒ | Jan 20 – Feb 18 |
| Pisces ♓ | Feb 19 – Mar 20 |
Worked example
Take a birth date of 10 May 2000 — the date the tool starts with.
Step 1: 10 May falls between 20 April and 20 May, so the Western sign is Taurus.
Step 2: at noon IST on 10 May 2000 the Sun's tropical longitude is 49.91 degrees.
Step 3: subtract the Lahiri ayanamsa for 2000, 23.86 degrees — the sidereal longitude is 49.91 − 23.86 = 26.05 degrees.
Step 4: 26.05 degrees lies between 0 and 30 degrees — sidereal Mesha (Aries).
So the same birthday is Taurus in the West and Mesha in the Vedic system — a textbook example of the ayanamsa shift.
FAQ
What is a sun sign?
Your sun sign is the zodiac sign the Sun was travelling through on your birthday. Because the Sun changes sign roughly once a month and stays in step with the calendar, the sun sign can be found from the birth date alone, without a birth time — unlike the Moon sign, which needs the date and time.
Why are my Western and Vedic sun signs different?
The Western (tropical) zodiac is fixed to the seasons and the Vedic (sidereal) zodiac is fixed to the stars. The two matched about 1,700 years ago, but precession has since moved them apart by roughly 24 degrees — most of one sign. So the Vedic Sun is usually found one sign earlier than the tropical Sun for the same birthday.
Which sun sign should I follow, Western or Vedic?
Neither system asks you to 'follow' a sign — it depends on the tradition you are reading. Western horoscope columns use the tropical sign. Indian astrology uses sidereal positions throughout, but even there the Sun sign is a minor factor: the Moon sign (rashi) and the rising sign (lagna) carry far more weight in a Vedic chart.
What if my birthday is on a cusp?
In the Western table, cusp days belong to whichever range contains the date — for example 20 May is listed as Taurus and 21 May as Gemini. In the Vedic calculation there is no fixed cusp date at all: the Sun crosses into a new sidereal sign when its longitude crosses the boundary, which happens around the 14th–15th of each month and shifts slightly by year.
Does the Vedic sun sign need my birth time?
Hardly ever. This tool reads the Sun at noon IST on your birth date. The Sun moves only about one degree a day, so the time of day matters only if you were born within roughly half a day of the moment the Sun changed sidereal signs — about one birthday in thirty for each boundary.
What ayanamsa does the Vedic calculation use?
The Lahiri ayanamsa, the standard for Indian panchangs and the value used by the Government of India's calendar committee. It grows by about 0.014 degrees (50 arc-seconds) per year, and for births in the year 2000 it is about 23.9 degrees.