Birth Chart Calculator

A birth chart is a map of the sky at the exact minute and place you were born. It shows where the Sun, the Moon and each planet sat in the zodiac, and how the horizon was angled at that moment. Everything else in astrology is read from that one picture.

Think of it as a portrait taken from the ground. Two people born on the same day share a sun sign, but if they were born six hours apart or in different cities, the rest of their charts can look very different. That is why your chart feels more like you than any horoscope column ever has.

Our calculator works out every position precisely from astronomical data, not from a lookup table of approximate dates. The planets are placed where they actually were, to the degree, for the moment you enter. The reading starts from real positions, which is exactly where a good reading should start.

Your sun sign is the core of you: what you are working towards, what lights you up, the version of yourself you recognise on a good day. It is the sign you already know, set by the date.

Your moon sign describes how you feel and what you need to feel safe. It is the part of you that shows up at home, when you are tired, or when something goes wrong. The Moon moves through a whole sign in about two and a half days, so the moon sign is where people born in the same week start to differ. A Leo sun with a Cancer moon wants the spotlight, then wants to go home and be looked after.

Your rising sign, or ascendant, is the sign that was coming up over the eastern horizon as you were born. It is your manner: how you walk into a room, the first impression people take away, the way you approach anything new. The rising sign changes roughly every two hours, which makes it the most personal of the three. It also sets the starting point for your houses.

The houses divide your chart into twelve areas of life, and they tell you where each planet's energy plays out. The signs describe how a planet behaves. The houses describe where you feel it.

The first house is you and your body. The second is money and what you value. The third is your daily conversations, siblings and neighbourhood. The fourth is home and family, the fifth is pleasure, romance and creativity, and the sixth is your daily work and habits. The seventh is partnership, the eighth is shared resources and intimacy, the ninth is travel, study and belief, the tenth is career and reputation, the eleventh is friends and causes, and the twelfth is rest, solitude and whatever you keep private.

So Venus in the tenth house brings charm to your working life, while Venus in the fourth brings it home. We use Placidus houses by default, the system most modern astrologers work with, which divides the sky by time. You can switch to Whole Sign houses, where each sign is one complete house, with a single tap.

Your birth time sets your rising sign and every house, so it is the difference between a sun-sign sketch and a chart that is truly yours. The Earth turns a full circle every day, which means the sign on the horizon, and so the whole house layout, shifts every few minutes.

It matters for the Moon too. Because the Moon moves quickly, a birth near the edge of a sign can put it in one sign in the morning and the next by evening. With a time, we place the Moon to the exact degree.

If you do not know your time, leave it blank. We set the chart for noon, which places the Sun and the slow planets accurately, and we hide the rising sign, the houses and the exact moon degree rather than guess them. The best sources for a birth time are a birth certificate, a hospital record, a baby book or a parent with a good memory. Once you have it, run the chart again and the full picture appears.

Your result leads with your sun, moon and rising signs, then lays out each planet, your balance of fire, earth, air and water, your balance of cardinal, fixed and mutable signs, and the key aspects. Here is what each sun sign brings to the centre of the chart.

• Aries: first through the door, honest, quick to start and quick to forgive.
• Taurus: steady, sensual, loyal, and very hard to rush.
• Gemini: curious, quick-witted, happiest with three conversations on the go.
• Cancer: protective, intuitive, the person who remembers how everyone takes their tea.
• Leo: warm, generous, made to be seen and to make others feel seen.
• Virgo: precise, helpful, quietly fixing what everyone else stepped over.
• Libra: fair, charming, always weighing how the room feels.
• Scorpio: intense, private, loyal to the bone once trust is earned.
• Sagittarius: restless, funny, searching for the bigger picture and the next horizon.
• Capricorn: patient, ambitious, building something that will still stand in ten years.
• Aquarius: independent, inventive, loyal to ideas and to friends in equal measure.
• Pisces: imaginative, empathetic, fluent in feelings other people have not named yet.

We calculate the true positions of the Sun, the Moon and the planets out to Pluto for the minute and place you give, then build the chart around them. Every degree comes from astronomical data, so the chart matches the sky as it actually was.

From your birth time and city we work out the ascendant and the midheaven, then draw the houses using Placidus or Whole Sign. We then look for the major aspects, the angles between planets that show how different parts of you work together: conjunctions, sextiles, squares, trines and oppositions. The Sun and the Moon get a slightly wider allowance, as they are the strongest points in any chart.

You also get a free daily note: where today's Moon is, set against your sun sign. When you want to see how your chart meets someone else's, the zodiac compatibility test takes it from there.