Stellar Parallax Distance Calculator

About this calculator

This calculator finds a star's distance from its parallax angle using the simple relation d (parsecs) = 1 / p (arcseconds), where p is the annual parallax — the tiny apparent shift in a star's position measured from opposite sides of Earth's orbit around the Sun. It also converts the result to light-years for a more familiar sense of scale.

Astronomers use stellar parallax as the most direct, geometry-based method of measuring cosmic distances, forming the base rung of the astronomical "distance ladder" that calibrates every other distance measurement technique used for more remote objects. Enter the parallax angle in arcseconds to get the distance in parsecs and light-years.