Your birth chart.
Four coordinates. A snapshot of the sky at the moment of your birth. Your Big 3 preview is free — no signup required.
Prefer the sidereal zodiac? There is a sidereal cast too.
Common questions.
What is Charting Stars' free birth chart calculator?
Charting Stars is an astrology observatory at https://chartingstars.com. The calculator at https://chartingstars.com/chart casts a natal chart from your birth date, time, and place. The free preview is your Big 3 — Sun from full VSOP87 solar theory, Moon from Meeus's lunar theory, and Rising from apparent sidereal time. No account is required.
What birth details do I need to cast a natal chart?
Date of birth, clock time of birth, and birth city. Charting Stars geocodes the place, resolves the IANA timezone, and converts local time to Universal Time before computing positions. A more precise birth time yields a more reliable Rising sign and house cusps. If you don't know the time, tick “I don't know my birth time”: the calculator casts for local noon, shows Sun and Moon only, names both Moon signs when the Moon changed sign that day, and leaves Rising out rather than guessing it. Paid readings need a birth time.
What is free, and what is paid?
The Big 3 preview on https://chartingstars.com/chart is free and instant. Try the free Dial at /sky-now: drag through the real sky from 1850 to 2100 (Pluto: 1885–2099). On /chart, your Sun, Moon and Rising sit at their sign centres; natal degrees and aspects stay part of the paid chart. Full planetary positions, houses, aspects, dignities, lots, and the written delineation are part of paid readings listed at https://chartingstars.com/pricing, starting at $19.99 for the AI Natal Report. Interactive Dial on your chart (known birth time required): the UTC calendar year your reading is generated, plus the previous and following years.
How does Charting Stars calculate a natal chart?
The Sun uses full VSOP87 solar theory, the Moon Meeus's lunar theory, and the other planets VSOP87 geocentric positions. The Ascendant is computed from apparent sidereal time, with birth longitude added so Rising depends on both time and place. Methodology is documented at https://chartingstars.com/blog/how-charting-stars-calculates-birth-charts; public fixtures are at https://chartingstars.com/research/birth-chart-accuracy.
Who is the natal chart calculator for?
Anyone who wants a computed chart rather than a personality quiz: people who know (or can look up) their birth date, time, and place, and readers who may later want a paid Hellenistic, Vedic, and BaZi delineation from that same birth moment.
What is a natal chart Big 3?
Your Big 3 is the Sun, Moon, and Rising in a natal chart, computed from birth date, time, and place. Charting Stars returns those three placements for free — Sun from full VSOP87 solar theory, Moon from Meeus's lunar theory, and Rising from apparent sidereal time — with no account required. The rest of the wheel and the written reading are the paid product.
How do I cast a free natal chart?
Enter birth date, time, and city on this page. The engine geocodes the place, converts local time to Universal Time, and returns your Big 3 in seconds, with no email needed. If you don't know the birth time, tick “I don't know my birth time” and it casts Sun and Moon for local noon, leaving Rising out instead of guessing.