Question 1

Is this natal chart calculator really free?

Accepted Answer

Yes. The calculator is completely free, with no sign-up, no email and no limits. The astronomical computation runs in your own browser.

Question 2

How accurate are the calculations?

Accepted Answer

Planetary longitudes are computed from the VSOP87 and ELP2000-82B theories and were verified against NASA JPL Horizons ephemeris data: agreement is within 0.7 arcminutes for the Sun through Pluto. This is the same class of precision used by professional astrology software.

Question 3

Why does the birth time matter so much?

Accepted Answer

The Earth rotates 15 degrees per hour, so the Ascendant and all house cusps shift by roughly one sign every two hours. Planet signs stay valid without a birth time, but house placements and the Ascendant need an accurate clock time.

Question 4

What is the difference between the Sun, Moon and Rising signs?

Accepted Answer

The Sun sign describes your core identity, the Moon sign your emotional needs, and the Rising (Ascendant) sign how you appear to others and meet new situations. Together they form the backbone of a natal chart reading.

Question 5

Which zodiac and house system do you use?

Accepted Answer

We use the tropical zodiac referenced to the ecliptic and equinox of date - the standard of Western astrology - with the Placidus house system by default. A Whole Sign option is available, and a Porphyry fallback is applied automatically at extreme latitudes.

Question 6

Is my birth data stored?

Accepted Answer

No. The chart is calculated entirely in your browser using JavaScript. Your birth date, time and place never leave your device - you can verify this with your browser's network inspector.

Question 7

Is astrology scientifically proven?

Accepted Answer

No. The astronomical positions we compute are precise science, but the interpretation of charts belongs to a symbolic tradition, not to established science. We present it for reflection and entertainment. See our methodology page for exactly what is calculated and how.

Free Natal Chart Calculator

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