Porphyrius Geocentric Birth Chart Calculator

This calculator uses Porphyrius house system and geocentric coordinate system.

The Porphyrius house system, named after the 3rd-century philosopher Porphyry, is a quadrant system that divides the space between the angles (Ascendant, IC, Descendant, MC) into three equal parts. It is one of the oldest house systems still in use today.

The geocentric system calculates planetary positions from the center of the Earth, which is the traditional and most widely used approach in Western astrology. This perspective shows the celestial bodies as they appear from Earth's center, providing the standard astrological view used by the vast majority of astrologers.

For more features including saving charts, transit charts, synastry charts, and more settings please use True Sky online astrology software.