Escape Velocity Calculator
Compute the minimum launch speed needed to break free of a planet or star using its mass and radius.
Planet preset
kg
m
11.186 km/s
- 1
2 × G × M
2 × 0 × 5,972,000,000,000,000,000,000,000 = 797,142,560,000,000 - 2
Divide by radius R
797,142,560,000,000 ÷ 6,371,000 = 125,120,477.1621 - 3
Square root → escape velocity
√(125,120,477.1621) = 11,185.7v = √(2GM/R) in m/s.
How does this calculator work?
Escape velocity is the minimum speed to break free of a body's gravity without further propulsion, found from v = √(2GM/R) where G is the gravitational constant, M the central mass, and R the launch radius. It is independent of the escaping object's mass. Earth's is about 11.2 km/s.
Formula
How this is calculated
Escape velocity is the speed at which an object's kinetic energy exactly balances the gravitational potential energy binding it to a body. Setting ½mv² = GMm/R and solving for v removes the projectile mass, giving v = √(2GM/R). Enter the central mass M in kilograms and the radius R in meters (the distance from the center to the launch point), or pick a planet preset to autofill realistic values.
The constant G is the universal gravitational constant, 6.674×10⁻¹¹ N·m²/kg². The result is reported in meters per second and kilometers per second. Because v depends on the square root of M/R, doubling the mass raises escape velocity by only about 41%, while a larger radius lowers it. The bar chart compares escape velocities across Earth, the Moon, Mars, Jupiter, and the Sun.
This model assumes a non-rotating, spherically symmetric body and ignores atmospheric drag and the gravity of other bodies. Escape velocity is the speed for a ballistic (unpowered) trajectory; a continuously powered craft can leave at any speed. Radius must be positive, and mass must be non-negative, otherwise no result is shown.
Frequently asked questions
No. The projectile mass cancels out, so a pebble and a spaceship need the same escape speed from the same point, ignoring air resistance.
About 11,186 m/s, or roughly 11.2 km/s, from the surface using Earth's mass of 5.972×10²⁴ kg and radius of 6,371 km.
Escape velocity decreases with distance from the center. Launching from altitude (larger R) lowers the required speed, which is why high-altitude or orbital launches are efficient.
Also known as
TG we-Calculate Editorial Team. (2026). Escape Velocity Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/escape-velocity-calculator
TG we-Calculate Editorial Team. "Escape Velocity Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/escape-velocity-calculator.
TG we-Calculate Editorial Team, "Escape Velocity Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/escape-velocity-calculator
@misc{wecalculate_escape_velocity_calculator, title = {Escape Velocity Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/escape-velocity-calculator}}, year = {2026}, note = {TG we-Calculate} }
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