Escape Velocity Calculator

Calculate escape velocity from any planet or body using mass and radius. Includes solar system presets, orbital velocity comparison, and delta-v requirements.

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m
Escape Velocity
Escape Velocity
Circular Orbital Velocity
Extended More scenarios, charts & detailed breakdown
kg
m
Escape Velocity
Orbital Velocity (surface)
Professional Full parameters & maximum detail
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m

Escape Velocities

Escape Velocity (surface)
Escape Velocity (altitude)

Orbital Velocities

Orbital Velocity (surface)
Orbital Velocity (altitude)

Mission Planning

Delta-v Gain from Altitude
Surface Gravity

How to Use This Calculator

  1. Enter the mass of the planet/body in kg and its radius in meters.
  2. Or switch to From Surface Gravity tab and enter g and radius.
  3. Use Solar System Presets to instantly see escape velocities for all major bodies.
  4. The Professional tier adds orbital velocity, delta-v from altitude, and surface gravity.

Formula

v = √(2GM/r)  |  G = 6.67430×10⁻¹¹ N·m²/kg²

From surface gravity: v = √(2gr)

Orbital velocity: v_orb = v_esc / √2

Example

Earth: M = 5.972×10²⁴ kg, r = 6.371×10⁶ m → v = √(2 × 6.674×10⁻¹¹ × 5.972×10²⁴ / 6.371×10⁶) = 11.19 km/s

Frequently Asked Questions

  • Escape velocity is the minimum speed an object needs to break free from a body's gravitational pull without further propulsion. It is v = √(2GM/r), where G is the gravitational constant, M is the body's mass, and r is its radius.
  • Earth's escape velocity from the surface is approximately 11.19 km/s (about 40,270 km/h). This is the speed needed to leave Earth without any additional thrust.
  • Escape velocity is exactly √2 times the circular orbital velocity at the same radius. So v_esc = v_orb × √2. At Earth's surface, orbital velocity would be ~7.91 km/s, and escape velocity is ~11.19 km/s.
  • Yes. If you know the surface gravity g and the body's radius r, use v = √(2gr). This is equivalent to the mass formula since g = GM/r².
  • Escape velocity itself is a gravitational quantity unaffected by atmosphere. However, atmospheric drag means rockets must launch faster to compensate for drag losses. The actual delta-v to orbit is typically 9–10 km/s for Earth.

Related Calculators

Sources & References (5)
  1. Escape Velocity — NASA Space Place — NASA
  2. University Physics Vol. 1, Ch. 13: Gravitation — OpenStax
  3. Escape Velocity — HyperPhysics — Georgia State University HyperPhysics
  4. Escape Velocity — Wikipedia (with NASA refs) — Wikipedia / NASA
  5. JPL Horizons System — Solar System Body Data — NASA Jet Propulsion Laboratory