Free tool
Birth Chart Calculator
This birth chart calculator shows the sky at the minute you were born. Enter your date, time and city, and ArcaLuna draws a natal chart with houses, planets and aspects, then explains your Sun, Moon and Ascendant below the wheel. Don't know your birth time? The chart still works, just without houses and the Ascendant.
Calculated on your device
Reading the wheel
Planets, houses and aspects
A natal chart calculator needs your date, time and place of birth. Here is what the wheel is made of.
- ☉︎Planets
The Sun, the Moon and eight planets each sit in a zodiac sign. The sign shows how a planet acts: Mars in Aries moves right away, Mars in Taurus once it has weighed everything.
- ⌂︎Houses
Twelve areas of life, from self and money to home, relationships and work. Houses depend on your exact time and place of birth.
- △︎Aspects
The angles between planets. Trines and sextiles (lavender lines) are where things come easily; squares and oppositions (rose lines) are where they take effort.
- ↑︎The Ascendant
The sign rising in the east at the minute you were born: the first impression you make and the start of the first house.
Questions
Birth chart questions
How does the birth chart calculator work?
Enter your date, time and city of birth and tap Draw my chart. The time zone and daylight saving rules for your birth date are filled in for you, including clock changes that were abolished long ago. The calculator is free and needs no sign-up.
Can I get a natal chart without a birth time?
Yes. Planets and aspects are calculated for noon, and houses and the Ascendant are hidden because they shift every few minutes. If the Moon changed sign that day, a note appears under your reading.
What's the difference between Whole Sign and Placidus houses?
In Whole Sign, the first house is the entire sign of your Ascendant and each next house is the next sign. Placidus divides the sky by the time each degree takes to rise, so houses come out in different sizes. The chart starts with Whole Sign; above 66° latitude Placidus is undefined and the switch tells you so.
How accurate is the chart?
Planet positions are checked against Swiss Ephemeris on 50 reference charts: they differ by less than 0.01°, the Ascendant by less than 0.001°. The biggest error usually comes from the birth time itself: 4 minutes off moves the Ascendant by about one degree.
Where does my data go?
Nowhere. The chart is calculated in your browser, and your date, time and place of birth are never sent to a server or stored. The city list loads in one piece, so even the city search makes no requests.
A birth chart helps you understand yourself better. It doesn't replace advice from a doctor, lawyer, financial adviser or therapist, and the decisions stay with you.
Cities: GeoNames, licensed under CC BY 4.0. The list is shortened and repackaged.
The ArcaLuna app
Your chart, every morning
In the app, the Today screen shows which planet touches your birth chart today, next to your daily card and the Moon. The Today screen is free, and the app is coming soon to the App Store and Google Play.
One email when the app is out. No other mailings.