Birth Chart Calculator
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A free natal chart with your Sun, Moon and rising sign, planets, houses, aspects and a chart wheel. No sign-up, and it works without a birth time.
Quick answer: A birth chart is a map of the Sun, Moon and planets at the moment you were born. Enter your birth date, time and place above for your Sun, Moon and rising sign, every planet from Mercury to Pluto, your houses and the major aspects, free and with no email. For example, a birth in London at noon on January 1, 2000 gives a Capricorn Sun, a Scorpio Moon and an Aries rising sign. No birth time? You still get your Sun sign and the planets.
Your Big Three
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📐 Formula
Each body's ecliptic longitude is computed for your birth moment in universal time: the Sun from Meeus' formula, the Moon and planets from Schlyter's orbital elements, Pluto from his periodic series. The sign is floor(longitude / 30). The Ascendant is atan2(cos RAMC, -(sin RAMC cos e + tan(latitude) sin e)), where RAMC is the local sidereal time and e the obliquity, and the Midheaven is atan2(sin RAMC, cos RAMC cos e). Whole Sign houses start at the sign of the Ascendant, and Equal houses at its exact degree. Aspects are angles of 0, 60, 90, 120 and 180 degrees within an orb.
How to Use the Birth Chart Calculator
Enter your birth date
Pick the month and day, and type the year between 1900 and 2099. All three are required.
Add your birth time and birth place
Both are optional. For the rising sign, houses and Midheaven you need the time and a place: pick a city, or enter latitude, longitude and a UTC offset.
Choose a house system
Whole Sign is the default. Equal houses start at the exact degree of the Ascendant.
Read your chart
See your Sun, Moon and rising sign, the chart wheel, the table of every placement with houses and retrograde status, and the major aspects.
Birth chart calculator: free, with Sun, Moon and rising sign
A birth chart, also called a natal chart, is a map of where the Sun, Moon and planets were in the sky at the moment you were born, seen from your place of birth. This calculator builds one in your browser from your birth date, time and place. You get your Sun, Moon and rising sign, the position of every planet from Mercury to Pluto, your houses, the major aspects between planets and a chart wheel. There is no sign-up and no email address, and your details are not sent anywhere. You can also use it with no birth time, as described below.
What you can work out without a birth time
Many people search for a birth chart calculator without a birth time, because they do not know theirs. You can still get most of a chart. Your Sun sign and the planets from Mercury outward depend on the date, and only change sign over weeks or years, so a missing time rarely changes them. The Moon changes sign every two and a half days, so it is usually fixed by the date too, and the calculator lists the possible signs if the Moon changed sign that day. What you lose without a birth time is the rising sign and the houses, because those turn with the Earth every day.
| Placement | What you need to know | How often it changes sign |
|---|---|---|
| Sun sign | Birth date | About every 30 days |
| Moon sign | Birth date, and the time if the Moon changes sign that day | About every 2.5 days |
| Rising sign (Ascendant) | Birth time and birth place | About every 2 hours |
| Houses and Midheaven | Birth time and birth place | Move with the rising sign |
| Mercury and Venus | Birth date | Every 2 to 5 weeks, longer when retrograde |
| Mars | Birth date | About every 6 weeks |
| Jupiter, Saturn, Uranus, Neptune, Pluto | Birth date | Years (Jupiter about a year, Pluto about 12 to 30) |
Sun, Moon and rising sign: your Big Three
Astrologers read the Sun, Moon and rising sign first. The Sun sign is the one most people know, and describes identity and what drives you. The Moon sign describes emotions and instinct. The rising sign, or Ascendant, is the sign that was coming up over the eastern horizon at the moment of birth, and describes how you come across to others and how you approach new situations. The calculator shows all three at the top. The Sun sign alone is the same answer you get from the zodiac sign calculator, which also handles birthdays on a sign boundary.
How to read your chart
The chart wheel is a circle of twelve signs with the rising sign on the left. Planets sit at the point on the circle that matches their position in the zodiac. The numbers inside the wheel are the houses. A planet tells you what is acting, the sign tells you how, and the house tells you where in your life. The planet table below lists what each planet stands for in traditional astrology.
| Planet | Represents |
|---|---|
| Sun | Identity, purpose, vitality |
| Moon | Emotions, instincts, what feels safe |
| Mercury | Thinking and communication |
| Venus | Love, values, taste |
| Mars | Drive, energy, anger |
| Jupiter | Growth, luck, beliefs |
| Saturn | Structure, limits, responsibility |
| Uranus | Change, surprise, independence |
| Neptune | Imagination, ideals, confusion |
| Pluto | Transformation, power, endings |
Birth chart houses: Whole Sign and Equal
The twelve houses are slices of the sky, counted from the rising sign. The calculator gives you two ways to cut them. In the Whole Sign system the rising sign is house 1, the next sign is house 2, and so on, so each house is one full sign. In the Equal system each house is exactly 30 degrees, starting at the exact degree of the Ascendant. Both are old and in current use. Whole Sign is the oldest Western method and is also the system used in Vedic astrology. The Placidus system, which some chart services use by default, makes houses of different sizes and breaks down near the polar circles. This calculator does not compute it. If your chart elsewhere shows different house numbers, the house system is the first thing to compare.
| House | Area of life |
|---|---|
| 1 | Self, appearance, first impressions |
| 2 | Money, possessions, values |
| 3 | Communication, siblings, short trips |
| 4 | Home, family, roots |
| 5 | Creativity, romance, play |
| 6 | Work routines, health, service |
| 7 | Partnerships, marriage, open rivals |
| 8 | Shared resources, intimacy, change |
| 9 | Travel, higher learning, beliefs |
| 10 | Career, reputation, public life |
| 11 | Friends, groups, hopes |
| 12 | Solitude, the unconscious, endings |
Why your birth time changes your rising sign
The Earth turns once a day, so every sign rises over the horizon in turn, each for about two hours on average, and at mid-latitudes a sign can last from about one to three hours depending on the sign and the season. That makes the rising sign the placement most sensitive to the birth time.
Worked example: January 1, 2000 in London
At 12:00 GMT on January 1, 2000 in London, the Sun is at 10 degrees 22 minutes of Capricorn, the Moon at 13 degrees 20 minutes of Scorpio, and the Ascendant at 24 degrees of Aries, with the Midheaven at about 9 degrees 29 minutes of Capricorn. One hour later, at 13:00 GMT, the Ascendant has moved to 22 degrees of Taurus, a different sign. The Sun is still Capricorn and the Moon is still Scorpio. Enter that date with the time 12:00 and London as the place and the calculator returns those positions. The same pair of hours in Sydney or Toronto would give different rising signs, because the Ascendant depends on where you were born.
Time zones and daylight saving: UK, Australia, Canada and the US
The calculator converts your birth time to universal time using the city's time zone and the daylight-saving rule that applied on that date, from your browser's time zone database. In the UK, British Summer Time runs from late March to late October. In most of Australia daylight saving runs from October to April, and Queensland, the Northern Territory and Western Australia (at most dates) do not use it. In Canada and the US it runs from March to November. For a birth place that is not in the list, enter its latitude and longitude and choose the UTC offset in force at the birth place on the birth date. A wrong offset moves the rising sign by whole hours.
How to find your birth time
The most reliable source is your birth certificate or the hospital record. A full-length certificate often has the time of birth, and some places issue it on request. If your family remembers a time, treat it as approximate. Astrologers who work with unknown birth times use a method called rectification, which tests candidate times against life events, and it is a skill of its own. Without a time, the calculator gives you everything that does not depend on it.
Retrograde planets
A planet is retrograde when, seen from Earth, it appears to move backwards against the stars for a while. It is an effect of the Earth overtaking or being overtaken by the planet, and the planet does not actually reverse. The table marks each planet as direct or retrograde at your birth moment. Sun and Moon are never retrograde.
Decans: the three ten-degree parts of each sign
Each sign is split into three decans of about ten days each. In the system used here, the first decan is ruled by the sign's own traditional ruler, and the second and third by the traditional rulers of the other two signs of the same element, in zodiac order. The result box shows the decan and its ruler for your Sun.
| Sign | Dates (about) | 1st decan (0 to 10 degrees) | 2nd decan (10 to 20) | 3rd decan (20 to 30) |
|---|---|---|---|---|
| Aries | Mar 20 to Apr 19 or 20 | Mars | the Sun | Jupiter |
| Taurus | Apr 19 or 20 to May 20 or 21 | Venus | Mercury | Saturn |
| Gemini | May 20 or 21 to Jun 20 or 21 | Mercury | Venus | Saturn |
| Cancer | Jun 20 or 21 to Jul 22 or 23 | the Moon | Mars | Jupiter |
| Leo | Jul 22 or 23 to Aug 22 or 23 | the Sun | Jupiter | Mars |
| Virgo | Aug 22 or 23 to Sep 22 or 23 | Mercury | Saturn | Venus |
| Libra | Sep 22 or 23 to Oct 22 or 23 | Venus | Saturn | Mercury |
| Scorpio | Oct 22 or 23 to Nov 21 or 22 | Mars | Jupiter | the Moon |
| Sagittarius | Nov 21 or 22 to Dec 21 or 22 | Jupiter | Mars | the Sun |
| Capricorn | Dec 21 or 22 to Jan 19 or 20 | Saturn | Venus | Mercury |
| Aquarius | Jan 19 or 20 to Feb 18 or 19 | Saturn | Mercury | Venus |
| Pisces | Feb 18 or 19 to Mar 20 | Jupiter | the Moon | Mars |
Tropical and sidereal charts
The chart on this page uses the tropical zodiac, which is measured from the March equinox and is what Western astrology uses. Vedic astrology uses the sidereal zodiac, measured against the stars, about 24 degrees back. If you want your Vedic Moon sign, nakshatra and starting dasha, use the Vedic astrology calculator.
What this calculator does not include
It does not compute asteroids or Chiron, the Placidus house system, transits, progressions or a synastry chart that overlays two people. For a quick comparison of two sun signs, the zodiac compatibility calculator scores any pair. The calculator uses the mean lunar node, as many Western charts do. Positions are for the geocentric zodiac in the ecliptic of the date.
Using this calculator in the US, UK, Australia and Canada
The chart works the same in all four countries, but your birth place and the clock rules on your birth date matter. The city list covers the main cities in each country, and the time zone and daylight saving for the date come from your browser's time zone database. Date formats differ: the UK, Australia and most of Canada write day first, so the month is chosen by name here to avoid mixing up April 3 and March 4. UK and Australian searchers often say star sign where US searchers say zodiac sign; the calculator gives the same Sun, Moon and rising sign either way.
Other birth-date calculators
If you want your Chinese animal and element, the Chinese zodiac calculator uses the Chinese New Year date. The Mayan day sign calculator reads the 260-day Tzolk'in.
Frequently Asked Questions
A birth chart calculator works out where the Sun, Moon and planets were at the moment of your birth, seen from your birth place. It uses your date, time and place to find each body's longitude along the zodiac, the Ascendant and the houses, then draws them on a wheel. This one runs in your browser and needs no sign-up.
Enter your birth date, time and birth place. The Sun and Moon signs come from your date, and the rising sign needs the time and place. The result shows all three at the top, followed by the full placements table and a chart wheel.
Yes. Leave the time blank. The calculator places the planets at noon on your birth date and shows every sign the Moon was in that day. You still get your Sun sign and the signs of the slower planets, but not your rising sign, Midheaven or houses, because those need the time.
The houses divide the chart into twelve areas of life, counted from the rising sign: self, money, communication, home, creativity, work and health, partnership, shared resources, beliefs, career, friends and the unconscious. The table on this page lists them. You can choose Whole Sign or Equal houses.
In Whole Sign houses each house is one full sign, starting with the rising sign. Placidus cuts houses of unequal size based on time, and fails near the polar circles. This calculator offers Whole Sign and Equal. If another chart shows different house numbers for the same birth data, the house system is the usual reason.
Your rising sign is the sign that was rising over the eastern horizon when you were born. Signs rise in turn about every two hours as the Earth turns, so a different birth time or birth place gives a different rising sign. That is why it cannot be found from the date alone.
Yes. It is free, there is no sign-up, and it never asks for your email address. The chart is computed in your browser, so your birth details are not sent or stored anywhere.
We compared the calculator's positions with NASA's JPL Horizons ephemeris on random dates between 1900 and 2100. The planets were within 0.05 degrees (about 3 arcminutes) and the Moon within 0.07 degrees. The Ascendant and Midheaven are exact for the time and place you enter, subject to the accuracy of your birth time.
Yes. It has the main cities in the UK, Australia and Canada, plus the US, Ireland, New Zealand and India. Each city carries its time zone, with daylight saving applied for the date you choose. For any other place, enter the latitude, longitude and UTC offset.
It gives you the positions, a chart wheel, the aspects and a plain-language guide to what planets, signs and houses represent, but not a personalized written reading. Reading a chart is interpretive and varies between astrologers, so we keep the output to what can be checked.
No. The chart on this page is tropical, as used in Western astrology. For the Vedic Moon sign, nakshatra and starting dasha, use the Vedic astrology calculator. It uses the sidereal zodiac with the Lahiri ayanamsa.
Not on this page. For a sun sign comparison with a percentage score, use the zodiac compatibility calculator. A synastry chart, which overlays two full charts, is not included.
No. It covers the Sun, Moon, Mercury to Pluto, the mean North Node, the Ascendant and the Midheaven. Chiron and the asteroids need orbit data that cannot be computed accurately from simple formulas, and transits are a separate feature.
A planet is retrograde when it appears to move backwards against the stars as seen from Earth. This is an effect of the Earth's own motion and the planet does not reverse direction. The table marks each planet from Mercury to Pluto as direct or retrograde at the moment you were born.
Sources & Methodology
There is no standards body for astrology, but the astronomy can be checked. The Sun's position uses the low-precision formula in Jean Meeus, Astronomical Algorithms, chapter 25. The Moon, and the planets Mercury to Neptune, use the orbital elements and perturbation terms in Paul Schlyter's "How to compute planetary positions", and Pluto uses the periodic series Schlyter gives for the years 1885 to 2099. The mean lunar node follows Meeus. We compared every body with NASA's JPL Horizons ephemeris (DE441, apparent geocentric ecliptic longitude) on 60 random dates for the Sun and Moon and 40 for each planet between 1900 and 2100: the largest difference was 0.007 degrees for the Sun, 0.07 degrees for the Moon and 0.05 degrees for the planets.
The Ascendant and Midheaven come from the standard spherical formulas using the sidereal time at your longitude and the mean obliquity of the ecliptic. We checked them geometrically for 400 random dates and places: the point on the ecliptic at the Ascendant lies on the horizon on the eastern side, and the Midheaven lies on the meridian. Time zones come from your browser's IANA time zone database. Planet meanings, house meanings, decan rulers and aspects follow traditional Western astrology, which is a cultural practice and is not scientifically validated.