Escape velocity does not depend on the mass of the escaping object, only on the planet’s mass and radius.
How to use the Escape Velocity Calculator
- Body mass
- Radius
Results update as you type, and every field accepts the units shown in its menu.
How it works
Multiply twice the gravitational constant by the body’s mass, divide by its radius and take the square root.
Inputs explained
| Field | What to enter |
|---|---|
| Body mass | In kg |
| Radius | Units: m, km |
What each result means
- Escape velocity = sqrt(2 × 6.6743e-11 × [Body mass] ÷ [Radius])
- Circular orbit speed at surface = [Escape velocity] ÷ sqrt(2)
Example values
How the main result changes when Body mass changes and everything else stays at the example values above:
| Body mass (kg) | Escape velocity (km/s) |
|---|---|
| 2.99e24 | 7.91 |
| 4.48e24 | 9.69 |
| 5.97e24 | 11.19 |
| 7.47e24 | 12.51 |
| 8.96e24 | 13.7 |
| 1.19e25 | 15.82 |
Formula
v = √(2 G M ÷ r)Worked example
Inputs — Body mass: 5.972e+24 kg; Radius: 6,371,000 m.
Results — Escape velocity = 11.19 km/s; Circular orbit speed at surface = 7.91 km/s.
Frequently asked questions
What is Earth’s escape velocity?
About 11.2 km/s.
Do rockets need to reach escape velocity?
Not to reach orbit, which needs about 7.8 km/s.
What formula does the Escape Velocity Calculator use?
v = √(2 G M ÷ r).