Zodiac sign calculator
Sun sign, Chinese animal and birthstone from a birth date.
The birth time matters only if you were born within a day of a sign change. The list holds major time zones only.
For entertainment only. Astrology is not science, and a sign does not predict anything about a person; the dates and the animal are calculated, their meanings are not.
Is astrology real?
No. Astrology is entertainment, not science. In the best-known controlled test, published in the journal Nature in 1985 (Shawn Carlson), astrologers who were respected by their peers could not match birth charts to personality profiles any better than chance. This page tells you which sign the Sun was in on a date, which is astronomy and can be calculated. What a sign means for your character or your future has no scientific support.
What are the dates of the zodiac signs?
The tropical zodiac divides the year into twelve 30-degree parts starting at the March equinox: Aries (about March 20 to April 19), Taurus (April 20 to May 20), Gemini (May 21 to June 20), Cancer (June 21 to July 22), Leo (July 23 to August 22), Virgo (August 23 to September 22), Libra (September 23 to October 22), Scorpio (October 23 to November 21), Sagittarius (November 22 to December 21), Capricorn (December 22 to January 19), Aquarius (January 20 to February 18) and Pisces (February 19 to March 20). The exact moment moves by up to a day from year to year; the table beside the result shows the moments for the year you enter.
What if I was born on the cusp?
The Sun changes sign at a precise moment, not at midnight, and that moment falls on a different clock time each year. In 2026, for example, the Sun entered Aquarius on January 20, 01:41 UTC. Two people born in New York on January 19, 2026 can have different signs: at 6 p.m. local time the Sun was still in Capricorn, and at 9 p.m., after the change, it was in Aquarius. Enter your birth time and place to get a firm answer. If you leave them blank, the calculator uses noon universal time and warns you when you are within a day of a change.
What are the elements and modalities?
The four elements (fire, earth, air, water) and three modalities (cardinal, fixed, mutable) are the traditional ways of grouping the twelve signs: each sign belongs to one element and one modality, and each combination appears once. Aries is fire and cardinal, Taurus is earth and fixed, Gemini is air and mutable, and the pattern repeats. They are part of the symbolism of astrology, not measured properties.
How is the Chinese zodiac animal worked out?
The animal depends on the Chinese lunar year, which begins on the lunar new year, not on January 1. The twelve animals repeat in the order Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Goat, Monkey, Rooster, Dog, Pig. If you were born before the lunar new year, your animal is the previous year's. The lunar new year of 2026 fell on February 17: a person born on February 10, 2026 is a Wood Snake (year 2025), and one born on February 17 is a Fire Horse.
Where do the lunar new year dates come from?
From the Gregorian-Lunar calendar conversion table of the Hong Kong Observatory, which covers 1901 to 2100. The first day of the first lunar month is read from each year's table. The Observatory notes that moon phases decades ahead are calculated to within a few minutes, so a new moon very close to midnight can shift a date by a day in a few far-off years (2057, 2089 and 2097 are the cases it lists).
Is there an official birthstone list?
There is no single official one. The list most used in the United States dates from 1912, when the American jewelry trade (the forerunner of Jewelers of America) published it, and has been extended since: alexandrite, citrine, tourmaline and zircon in 1952, tanzanite in 2002 and spinel in 2016. Other organizations and countries differ, for instance in whether moonstone is a June stone, so this page lists the first stone with the alternates beside it.
How the sign is calculated
A sun sign is a place on the ecliptic, the path the Sun appears to follow through the year, measured from the March equinox. Zero degrees is the start of Aries, 30 degrees the start of Taurus and so on. The calculator finds the Sun's ecliptic longitude on your birth date from a standard low-precision formula (Jean Meeus, Astronomical Algorithms, chapter 25), good to about 0.01 degrees, and the sign is the longitude divided by 30. It reproduces the equinox and solstice times published by the US Naval Observatory to within ten minutes: the 2026 March equinox, for example, is March 20, 14:37 UTC here and 14:46 UT in the Naval Observatory's table.
Worked example
Born May 15, 1990. The Sun was at 54.4 degrees of ecliptic longitude, in the 30 to 60 degree band: Taurus, Earth, Fixed. The lunar new year of 1990 fell on January 27, so the birth date is after it: the Chinese year is 1990, a Metal Horse (Yang, Geng-wu). May's birthstone is Emerald. For a year to look ahead, the animals for the next three years are 2026: Fire Horse, 2027: Fire Goat, 2028: Earth Monkey. The table beside the result gives the 2026 entry moments: Aries March 20, 14:37 UTC, Leo July 22, 19:13 UTC, Virgo August 23, 02:22 UTC and Pisces February 18, 15:46 UTC.
Why the dates differ between websites
Because a sign changes at a moment, and because the moment shifts. Over a four-year cycle the entry into a sign moves by about a day and then snaps back at the leap day. Websites print one fixed table, rounded to a day, and those tables disagree by a day at the edges. Some astrologers use the sidereal zodiac, which is shifted by roughly 24 degrees from the tropical one because of the precession of the equinoxes and gives a different sign for most people. This page uses the tropical zodiac, the one used in Western newspaper horoscopes, which is tied to the seasons and not to the constellations.
Limits
The calculator tells you where the Sun was; it does not draw a birth chart, find your Moon or rising sign, or interpret anything. It covers 1901 to 2100 because the Chinese new year table does. Time zones for birth times come from a fixed list of major zones, so a smaller place should be entered as the zone it follows. For the Chinese year the page uses the lunar new year, which is the cutoff for the Hong Kong Observatory's table and for most calendars, although some practitioners start the animal year at a solar term in early February instead. Birth flowers are left out because no official list could be found.
Sources and related calculators
Sources: J. Meeus, Astronomical Algorithms (2nd ed., 1998), chapter 25, solar coordinates, checked against the US Naval Observatory equinox and solstice times (aa.usno.navy.mil, 2000 and 2026); Hong Kong Observatory, Gregorian-Lunar Calendar Conversion Table 1901–2100 (data used under the terms of data.gov.hk, source: Hong Kong Observatory); S. Carlson, “A double-blind test of astrology,” Nature 318, 419–425 (1985); birthstone list as published by Jewelers of America and the American Gem Trade Association, with additions in 1952, 2002 and 2016. Related: age calculator, moon phase calculator, generation calculator and countdown calculator.