Free birth chart calculator
Natal Birth Chart Calculator
A natal chart, or birth chart, is a map of the sky at the exact moment and place you were born. It shows where the Sun, Moon and planets were, which sign was rising on the eastern horizon, and how all of it falls across the twelve houses of your life. Enter your birth details below to see your whole chart, with readings for your big three and your North Node.
Go deeper
Your chart is a story still being written
These are the first lines. In an evolutionary natal reading, we read the whole chart together: where you’ve come from, what you’re here to grow into, and what’s moving in your life right now.
Explore an evolutionary natal reading
Don’t know your birth time? Find your rising with me.
New to evolutionary astrology? Read where to begin.
Curious about your work and money? See your four maps with the Midheaven calculator.
The First Light
A letter at each new moon: what this cycle is asking of you, and a question to carry through the weeks ahead.
How to read your natal chart
New to this way of reading a chart? Start with What is evolutionary astrology?
What are the Sun, Moon and Rising signs?
Your Sun, Moon and Rising signs are often called your “big three.” Your Sun sign describes the core of who you are becoming: your vitality and purpose. Your Moon sign describes what you need to feel safe, and your emotional world. Your Rising sign, or Ascendant, is the sign that was rising on the eastern horizon at your birth. It describes how you meet the world, and it sets up the houses of your whole chart.
What is the North Node?
The North Node is the point where the Moon’s path crossed the Sun’s path heading north at your birth. In evolutionary astrology, it points toward the growth you’re here for, while the South Node, directly opposite, describes what is deeply familiar.
What are the houses?
The twelve houses divide the sky into areas of life: self, money and values, communication, home, creativity, work and health, partnership, intimacy, meaning, vocation, community and the inner world. A planet’s house shows where in your life its story plays out. Houses need an exact birth time.
What does the ℞ symbol mean?
It marks a planet that appeared to move backward, or retrograde, when you were born. In evolutionary astrology, a retrograde planet often works more inwardly, asking to be understood on your own terms.
How this calculator works
We believe a calculator should show its work. Here’s exactly how your chart is calculated:
- Planets, Sun and Moon: calculated with Astronomy Engine, an open-source astronomy library tested against NASA JPL and U.S. Naval Observatory data and accurate to within one arcminute. Positions are apparent, geocentric and in the tropical zodiac.
- Rising sign, Midheaven and houses: calculated with the standard formulas in Jean Meeus’s Astronomical Algorithms, using the exact latitude and longitude of your birthplace. Houses use the Placidus system. Beyond the polar circles, where Placidus can’t be calculated, Porphyry houses are used instead.
- Lunar nodes: the mean North Node is shown. If the true node falls in a different sign, your results say so.
- Birthplace and time zone: birthplaces come from the GeoNames database (CC BY), and daylight-saving rules from the international IANA time zone database built into your browser.
- Tested: before launch, this calculator was checked against Swiss Ephemeris, the reference used by professional astrology software, on 20,000 randomly chosen births. Every planet, rising sign, Midheaven and house cusp landed in the same sign, with positions matching to within a third of an arcminute.
Frequently asked questions
Is this natal chart calculator free?
Yes. There’s no sign-up, and your birth details never leave your browser.
Do I need my exact birth time?
For your rising sign and houses, yes. The rising sign changes about every two hours. Without a birth time, you’ll still see your Sun, Moon and every planet’s sign, and the calculator will tell you if your Moon changed signs that day. If you don’t know it, a chart rectification can estimate your rising sign.
Where do I find my birth time?
It’s usually on a long-form birth certificate. A hospital record or a parent’s memory can also help.
What’s the difference between a natal chart and a birth chart?
Nothing. They’re two names for the same map of the sky at your birth.
Why is my rising sign different on another site?
Usually because of the birth time, the time zone or daylight-saving time used. Your results show the exact time zone this calculator used, so you can check it against your birth certificate.
Which house system does this use?
Placidus, the most widely used system, and the one I work with in readings.
Created by Christine Alexander, evolutionary astrologer. Birthplace data © GeoNames, CC BY.