Physics

Escape Velocity Calculator

Calculate the speed needed to escape a body's gravity entirely, with the circular orbital speed for comparison.

kg
m
Escape velocity
—
v_escape = √(2GM / r), which is exactly √2 × the circular orbital speedMass of the bodykgRadiusm

Earth's number, and why it is not the whole story

For Earth the result is 11.19 km/s. No rocket actually reaches that speed at the surface, because escape velocity assumes a single unpowered impulse with no atmosphere. Real launches burn continuously, climb out of the thickest air first, and gain about 0.46 km/s free from Earth's rotation by launching eastward.

The formula

v_escape = √(2GM / r), which is exactly √2 × the circular orbital speed

Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.

How to use the Escape Velocity Calculator

  1. Fill in each field with your own figures — the defaults are only there as an example.
  2. The result updates as you type, so there is no button to press.
  3. Check the breakdown under the main result for the supporting numbers.
  4. Use the copy button to take the result with you, or share the link to reload the same inputs.

Escape Velocity Calculator — frequently asked questions

Is this escape velocity calculator free to use?

Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.

How accurate is the result?

The maths is exact for the formula shown on the page. Accuracy in the real world depends on your inputs and on assumptions the formula cannot see, so treat the output as a well-grounded estimate rather than a quote.

Can I use it on my phone?

Yes. The page is responsive, weighs a few kilobytes and works offline once loaded, so it behaves the same on a phone as on a desktop.

What people search for

This page answers each of these searches. They are the exact phrases visitors use to find the escape velocity calculator.

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About this calculator

Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.

Last reviewed August 23, 2026 · Calculation runs client-side · No data collected · Report an error