Birth chart calculator
Enter date, time, and birth coordinates. Computes ascendant, midheaven, planet positions in the tropical zodiac, whole-sign house placements, and major aspects. Birth data stays in your browser.
About this calculator
Planetary positions are computed with Astronomy Engine (MIT-licensed VSOP87 + ELP-2000). Ascendant and midheaven are derived from local sidereal time and the mean obliquity of the ecliptic at the birth instant.
Houses default to Whole-Sign— the Hellenistic convention where each house corresponds exactly to one zodiac sign, starting from the ascendant's sign. Placidus, the standard quadrant system, is also available from the house-system selector; its intermediate cusps are solved iteratively from each point's diurnal semi-arc, falling back to whole-sign for circumpolar cusps at extreme latitudes. See methodology for the trade-offs.
Aspects are major (conjunction / opposition / trine / square / sextile) and minor (semisextile / semisquare / sesquiquadrate / quincunx / quintile / biquintile), with classical orbs from cited sources.
Reference, not advice
This is cultural and astronomical reference, not personal prediction or advice.
This calculator is a reference tool. Astrology is documented cultural and historical material; it is not a scientifically demonstrated method of prediction. See the disclaimer.
Last reviewed .