Escape Velocity Calculator
Enter a celestial body’s mass and radius to calculate its escape velocity.
Escape Velocity Calculator
Calculate the escape velocity needed to break free of a celestial body’s gravity from its mass and radius.
Escape velocity is the minimum speed an object needs to break free of a celestial body’s gravity without further propulsion. It depends only on the body’s mass and radius — the default values here are Earth’s, giving the well-known result of about 11.2 km/s.
Example
- With the default values shown above, this calculator returns: Escape Velocity ≈ 11,186.0; Escape Velocity (km/s) ≈ 11.186.
Frequently Asked Questions
What is Earth’s escape velocity?
About 11.2 km/s (roughly 40,270 km/h) — the default values in this calculator are Earth’s mass and radius, so you can see this result directly.
Why does escape velocity not depend on the object escaping?
Escape velocity is derived purely from the gravitational body’s mass and radius — the mass of the escaping object cancels out of the equation entirely, so a pebble and a spacecraft need the same escape velocity.