NumberCals

Escape Velocity Calculator

Calculate the minimum speed needed to escape a celestial body's gravitational pull.

About this calculator

The Escape Velocity Calculator on NumberCals is a free, mobile-friendly tool for anyone needing to calculate the minimum speed needed to escape a celestial body's gravitational pull. Enter your values in the form below and the result is computed instantly — no sign-up, no installation, no waiting.

Formula used

v_escape = √(2GM/r)

What you'll need

  • Celestial Body
  • Mass (kg, only if 'Custom') (e.g. 5.972e24)
  • Radius (m, only if 'Custom') (e.g. 6371000)

What you'll get

  • Escape Velocity (m/s)
  • Escape Velocity (km/s)
  • Escape Velocity (km/h)
Formula
v_escape = √(2GM/r)

Frequently Asked Questions

What's Earth's escape velocity? +

About 11.2 km/s (40,270 km/h). That's the speed needed to leave Earth's gravity entirely with no further propulsion — though real spacecraft don't actually need this speed, because they keep thrusting.

Black hole? +

A black hole's escape velocity exceeds the speed of light — which is why light cannot escape from inside the event horizon.

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