To leave Earth for good without further thrust, you would need 11.2 km/s. On the Moon only 2.4 km/s is enough; on Jupiter about 60 km/s. Escape velocity is √2 times the speed of a circular orbit at the same distance.
How to use the Escape Velocity Calculator
- Celestial body
- Mass M
- Radius R
Results update as you type, every field has its own unit menu, and everything is calculated in your browser.
How it works
Pick a celestial body or enter a custom mass and radius.
Inputs explained
| Field | What to enter |
|---|---|
| Celestial body | Choose one: Earth, Moon, Mars, Mercury … |
| Mass M | Units: kg, M⊕, M☉ |
| Radius R | Units: km, m, mi, nmi, ft |
What each result means
- Escape velocity = sqrt(2×6.6743e-11×[M]÷[R])
- First cosmic velocity (surface orbit) = sqrt(6.6743e-11×[M]÷[R])
- Surface gravity = 6.6743e-11×[M]÷[R]^2
Example values
How the main result changes when Mass M changes and everything else stays at the example values above:
| Mass M (kg) | Escape velocity (km/s) |
|---|---|
| 2.99e24 | 11.1862 |
| 4.48e24 | 11.1862 |
| 5.97e24 | 11.1862 |
| 7.47e24 | 11.1862 |
| 8.96e24 | 11.1862 |
| 1.19e25 | 11.1862 |
Formula
v_e = √(2GM/R), v_1 = √(GM/R)
Worked example
Inputs: Celestial body: Earth.
Results: Escape velocity = 11.18617 km/s; First cosmic velocity (surface orbit) = 7.90981 km/s; Surface gravity = 9.8203 m/s².
Key terms
- First cosmic velocity
- Speed for a circular orbit at the surface.
Frequently asked questions
What is Earth's escape velocity?
11.19 km/s (about 40,000 km/h).
Does escape velocity depend on the object's mass?
No, only on the planet's mass and radius.
Why don't rockets reach escape velocity at launch?
They accelerate gradually; escape speed decreases with altitude.
What has an escape velocity above c?
A black hole, inside its event horizon.