Escape Velocity Calculator

About this calculator

This calculator finds escape velocity — the minimum speed an object needs to break free of a planet or moon's gravity without further propulsion — using v = √(2GM/r), where G is the gravitational constant, M is the body's mass, and r is the distance from its center. Earth's escape velocity works out to about 11.2 km/s.

It's a staple of astronomy and physics courses, used by students checking textbook problems and by space enthusiasts comparing how much harder it is to leave a massive planet like Jupiter versus a small moon. Rocket engineers use the same formula, in more detailed form, to plan how much thrust a launch needs.