Escape Velocity Calculator
Calculate the speed needed to escape a planet's gravitational field.
⚡ Physics📐 v_esc = √(2GM/r)
Planet mass (kg)
Planet radius (m)
Please enter valid values.
Formula & Reference
| Variable | Formula | Units |
|---|---|---|
| Escape Velocity Calculator | v_esc = √(2GM/r) | km/s |
Step-by-Step Examples
Example 1
Earth
M=5.97e24 kg, r=6.37e6 m.
- v_esc = 11.19 km/s = 40,270 km/h
✓ 11.19 km/s
Example 2
Moon
M=7.35e22 kg, r=1.74e6 m.
- v_esc = 2.38 km/s — much easier to leave!
✓ 2.38 km/s
Example 3
Sun
M=1.99e30 kg, r=6.96e8 m.
- v_esc = 617.5 km/s
✓ 617.5 km/s
Real-World Applications
Physics Students
Understand escape velocity from any body.
Space Engineers
Calculate delta-v for spacecraft missions.
Astronomers
Determine gravitational influence of celestial bodies.
Teachers
Demonstrate rocket science physics.
Common Mistakes to Avoid
⚠️
Rockets don't need instant escape velocity
Rockets build speed during burn. Atmospheric drag is a separate consideration.
⚠️
Altitude matters
Escape velocity decreases with altitude: v = √(2GM/r) where r is distance from center.
Frequently Asked Questions
Earth escape velocity? ▾
11.19 km/s from the surface without further propulsion.
How does escape velocity relate to black holes? ▾
A black hole forms when escape velocity exceeds c (speed of light). Nothing can escape.
Moon landing fuel advantage? ▾
Moon escape velocity (2.38 km/s) is much lower than Earth's (11.19 km/s), requiring far less fuel to return.