A MAP OF THE SKY. A LITTLE INSIGHT INTO YOU.
Free birth chart
calculator.
There’s a whole universe beyond your Sun sign. Discover your Moon, rising sign and planetary placements, with a personal reading from Astraia.
Meet your chartA SNAPSHOT OF YOUR BEGINNING
What is a birth chart?
A birth chart, also called a natal chart, maps the positions of the Sun, Moon and planets at the moment and place you were born. In astrology, each placement offers a different lens on your identity, emotional needs, relationships and ways of moving through life.
Your Sun sign is one part of that picture. Your Moon speaks to your inner world, your rising sign to how you meet new experiences, and the other planets add their own themes. This free birth chart analyser brings those placements together with the interpretations you’ll find in Astraia.
Explore your Sun, Moon and rising signs ↗A LITTLE CONTEXT GOES A LONG WAY
Get to know your chart.
How to read your birth chart
Learn how to read a birth chart step by step, from Sun, Moon and rising signs to planets and houses, with a free chart to explore your placements.
THE BIG THREESun, Moon and rising signs, explained
Understand the difference between your Sun, Moon and rising signs, why your birth time matters, and how to calculate your big three for free.
THE TWELVE HOUSESThe 12 houses in astrology
Explore what the twelve astrology houses mean, how whole-sign houses work, and why an accurate birth time matters for your natal chart.
YOUR PLANETARY PLACEMENTSWhat the planets mean in astrology
A beginner’s guide to the Sun, Moon, Mercury, Venus, Mars and outer planets in your birth chart, with links to calculate your own placements.
UNKNOWN BIRTH TIMEBirth chart without a birth time: what can you find out?
Learn what a birth chart without a birth time can show, why rising and houses are uncertain, and how to read two possible Moon signs responsibly.
YOUR CONNECTIONSBirth chart compatibility: how to compare two charts
Explore birth chart compatibility through Moon, Venus, Mars and communication themes. Learn what synastry means and the limits of an astrology reading.
GOOD QUESTIONS
A little clarity,
before you begin.
Is this birth chart calculator really free?
Yes. Calculate your chart and read all ten planetary sign interpretations, your rising sign and your whole-sign house placements for free. No email, account or payment is required. Astraia is also free to download, with optional in-app purchases. An email address is only required if you choose to download the optional PDF.
What do I need to calculate my birth chart?
Enter your birth date, the local time recorded at birth, and your birthplace. Choose the correct city and country from the results. Its time zone is used to account for historical clock changes. If your town is missing, you can enter coordinates and an IANA time zone manually.
Can I get a birth chart without a birth time?
Yes, with limits. Select “I don’t know my birth time” for a partial chart calculated at local noon. Rising sign and houses are omitted. If a planet changes signs during your birth date, both possible signs are shown; its exact degree is not presented as certain.
What is the difference between a birth chart and a natal chart?
They are two names for the same thing: a map of the sky for your birth date, time and place. Astrology interprets that map through planets, zodiac signs, houses and the relationships between them.
Which zodiac and house system does this calculator use?
This calculator uses the tropical zodiac, geocentric planetary positions and whole-sign houses. The sign containing your ascendant becomes the entire first house. Astraia’s mobile chart also has other chart features and uses Porphyry houses, so house assignments can differ.
Why might my results differ from another calculator?
First check the date, AM/PM, selected city and time zone. Tropical and sidereal zodiacs give different results, and house systems divide a chart differently. Placements very close to a sign boundary can also differ with the calculation method or an approximate birth time.
Are my birth details saved?
The calculator runs in your browser. Your birth details are not sent to a chart API, put into a shareable URL, or saved by this tool. City data and Astraia’s readings load from this website. Refreshing the page clears your chart.
BEHIND YOUR CHART
How we calculate your birth chart
We use Astronomy Engine to calculate geocentric planetary longitudes in the tropical zodiac. The rising sign is the eastern intersection of the horizon and ecliptic at your birth location. This website uses whole-sign houses; Astraia’s mobile natal chart uses Porphyry houses and an approximate planetary calculation, so house assignments and placements very near sign boundaries may differ.
Birth times are converted using the selected location’s IANA time zone, including available historical clock changes. City centres provide approximate coordinates. For a more precise location, use the manual coordinates option; historical results depend on the time-zone data supported by your browser. City data is provided by city-timezones. Interpretations come from Astraia’s English natal-chart library.
Astrology is an interpretive tradition for self-reflection, not a scientifically validated way to assess personality or predict events.
A LITTLE MORE PERSPECTIVE, EVERY DAY
Your universe, in your pocket.
Explore your birth chart, check in with your horoscope, draw tarot and discover your connections. Download Astraia for free.
Available on iOS and Android. Optional in-app purchases.