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

VariableFormulaUnits
Escape Velocity Calculatorv_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

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.

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