Escape Velocity Calculator
Escape and orbital speed for any planet, moon or star.
About this tool
Choose a body or enter a custom mass and radius, and an altitude if you like. The tool gives escape velocity in km/s, km/h and mph, the circular orbit speed, the gravity at that distance and the body's Schwarzschild radius.
What escape velocity means
Escape velocity is the minimum speed an object needs to coast away from a body and never fall back, ignoring air resistance and propulsion: v = โ(2GM รท r), where M is the body's mass and r the distance from its centre. From Earth's surface it's about 11.2 km/s (40,300 km/h); from the Moon 2.4 km/s, from Mars 5.0 km/s and from Jupiter about 60 km/s. It's always โ2 times the speed of a circular orbit at the same distance, which is 7.9 km/s just above Earth, and it falls the higher you start. A related idea is the Schwarzschild radius, 2GM รท cยฒ, the size a mass would have to be compressed to for its escape velocity to equal the speed of light, making a black hole: about 9 mm for Earth and 3 km for the Sun. Honest limits: rockets don't need escape speed at launch because they keep burning fuel; the calculation ignores atmosphere, the body's rotation, which helps eastward launches, and the pull of other bodies. The orbital period calculator and the gravitational force calculator are related.
Frequently asked questions
What is Earth's escape velocity?
About 11.2 km/s, or roughly 40,300 km/h (25,000 mph), from the surface.
What is the escape velocity formula?
v = โ(2GM รท r), with G the gravitational constant, M the body's mass and r the distance from its centre.
Does escape velocity depend on the object's mass?
No. It's the same for a pebble or a spacecraft; only the body being escaped from matters.
What is the relation between orbital and escape velocity?
Escape velocity is โ2 (about 1.414) times the circular orbital velocity at the same distance.
Is my data sent anywhere?
No. Everything is calculated in your browser, and nothing is stored or sent.