How Pull My Chart Calculates Astrology Charts
Pull My Chart separates astronomical calculation from astrological interpretation. This page explains what the calculators do, which settings can change a result, and where uncertainty enters the chart.
The calculation layer
Planetary longitudes and speeds are calculated with Swiss Ephemeris. A birth date, clock time, time-zone offset, latitude, and longitude are converted into a single astronomical moment before planetary positions are calculated.
The natal chart defaults to the tropical zodiac and Placidus houses. It also offers a sidereal zodiac mode and Whole Sign houses. Changing the zodiac or house system can change sign or house labels even when the underlying birth moment stays the same.
What an accurate birth time changes
The Ascendant, Midheaven, house cusps, and astrocartography angles are time-sensitive. A small time error may move an angle by several degrees; a larger error can change the rising sign or house placement. If your time is unknown, treat angle and house results as provisional.
Interpretation boundaries
Astrological interpretations describe a symbolic tradition, not a scientifically validated prediction of personality or events. They are provided for reflection and entertainment and are not medical, legal, financial, or psychological advice. A single placement page is a starting point, not a verdict.
Privacy and reproducibility
Chart inputs are not attached to an email subscription or transferred to a recommended reader or shop. To reproduce a result, use the same birth date, local clock time, location, time-zone handling, zodiac mode, and house system.
Generate a free natal chart · Birth-time accuracy guide · Privacy policy