Escape Velocity Calculator
Enter mass in kilograms and radius in metres to calculate v = √(2GM/r).
A QUICK WALKTHROUGH
How to use this tool
- Enter mass in kg and radius in metres.
- Review the ideal-model assumptions.
- Calculate and read the velocity in m/s and km/s.
Ideal model assumptions
The formula assumes a spherical body, uniform gravitational parameter, no atmosphere, and no rotation. It ignores terrain, drag, launch latitude, guidance, and other mission effects.
GOOD TO KNOW
Common questions
Does this plan a launch?
No. It is an ideal arithmetic calculation, not a spacecraft-planning guarantee.
What units are required?
Enter mass in kilograms and radius in metres; output is metres per second and kilometres per second.