Free birth chart calculator (natal chart)

A birth chart, also called a natal chart, is a map of the sky at the exact moment and place you were born: the Sun, the Moon and the eight planets, each set in one of the twelve zodiac signs and one of the twelve houses. The positions are astronomy. What each one means is astrological tradition.

The wheel above shows that map the way astrologers have drawn it for centuries: the zodiac around the rim, the horizon running left to right with your rising sign at the left edge, and every planet placed at the exact degree it occupied over your birthplace.

The planets move slowly, but the sky itself turns once every day. Your rising sign, the sign climbing the eastern horizon as you were born, changes roughly every two hours, and the whole house wheel turns with it. Two babies born in the same city on the same day, twelve hours apart, share most planets yet live them through entirely different houses.

That is why this calculator asks for the minute and the city, and converts your local birth time to universal time using the time zone rules that applied on that date, daylight saving included. If the time is unknown, it computes a noon chart and says so: the planets hold, the houses stay provisional.

Start with the big three: your Sun for the core of who you are, your Moon for how you feel, and your rising sign for how you meet the world. They frame everything else on the wheel.

Then read each planet by the sign it is in and the house it sits in, sign for how it acts and house for where it plays out. The aspects, the lines drawn across the wheel, show which parts of you work together and which pull against each other. You do not have to take it in all at once; a chart rewards slow reading.

Houses divide the sky into twelve rooms of life: self, money, communication, home, and onward. Placidus, the modern default, divides them by time and produces houses of uneven size. Whole sign, the oldest method, gives each sign one full house. Koch is popular in German-speaking countries, and equal houses, common in British astrology, count 30 degrees each from the Ascendant. This calculator draws all four, one switch apart, with Placidus selected by default.

None is wrong. Placidus sharpens charts at middle latitudes, while whole sign stays reliable everywhere and has seen a revival among traditional astrologers. When a planet changes houses between systems, read it as living in both rooms. Under every chart the calculator names the house system it used, and why charts differ explains how house systems and zodiac types shape a chart. For a longer walk through all twelve, read astrology houses explained.

Every position is computed from first principles: a full planetary theory for the planets, a high-precision lunar theory for the Moon, and the classical formulas for the Ascendant, the Midheaven and the house cusps, checked against professional ephemerides to within one arcminute. We test the engine against NASA JPL's Horizons ephemeris; the accuracy page shows the comparison.

The chart is calculated in your browser, from a world city dataset and time zone history that ship with the page. To show the first line of today's reading, your birth details are sent once to our server, which does not store them; the place search sends only the place name you type. A share link carries the birth details inside it, and nothing is stored on our side.

Astrologers read a birth chart as a portrait of character and timing, a language for reflecting on yourself and the people around you. It is a mirror to think with, and many people find it a useful one.

It does not predict fixed events or decide anything for you. The astronomy behind the wheel is exact, and the meanings are a tradition laid over it, so take the chart as a prompt for reflection rather than a forecast.