Escape Velocity Calculator
Escape velocity is the minimum speed an object must reach to break free from a celestial body's gravitational pull without further propulsion. Calculated using ve = sqrt(2GM/r), it depends only on the body's mass and the distance from its center. This calculator includes presets for major solar system bodies or lets you enter custom values.
The escape velocity formula ve = √(2GM/r) is derived from conservation of energy. An object at distance r from a mass M has gravitational potential energy -GMm/r. To escape to infinity (where PE = 0), its kinetic energy ½mv² must equal or exceed |GMm/r|. The mass of the escaping object cancels out, meaning escape velocity is the same for a pebble or a spacecraft.
Earth's escape velocity at the surface is about 11.2 km/s (40,270 km/h). The Moon's is only 2.4 km/s due to its smaller mass, which is why the Moon has lost most of its atmosphere. Jupiter's enormous mass gives it an escape velocity of about 59.5 km/s, while the Sun's surface escape velocity exceeds 617 km/s.
Escape velocity assumes no air resistance and no additional propulsion after the initial launch. In practice, rockets use sustained thrust rather than achieving escape velocity at the surface, and atmospheric drag must be accounted for. The concept remains fundamental to orbital mechanics, astrophysics, and understanding why different bodies retain different atmospheres.