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Escape velocity calculator

Compute the escape velocity of a body from its mass and radius.

Related tools

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Orbital velocity calculatorCompute the circular orbital velocity around a body from its mass and orbit radius.Angular Velocity CalculatorConvert RPM, rad/s, Hz and period, or derive ω from a linear speed and radius — with tangential speed and centripetal acceleration.Velocity CalculatorFind velocity, distance, time, relative or angular-to-linear speed — five modes, any units.Centripetal force calculatorCompute the centripetal force on an object moving in a circle (F = mv²/r).Orbital period calculatorCompute how long an object takes to orbit a body from the orbit radius and mass.Kinetic energy calculatorCompute kinetic energy from mass and velocity (½mv²).Momentum calculatorCompute momentum from mass and velocity (p = mv).Acceleration calculatorCompute acceleration from the change in velocity over time.

The Escape velocity calculator turns Mass (×10²⁴ kg), Radius (km) into Escape velocity (km/s), instantly and for free. For instance, with Mass (×10²⁴ kg) = 5.972 and Radius (km) = 6,371 it returns Escape velocity (km/s) = 11.186.

How to use it

  1. Enter your values: Mass (×10²⁴ kg), Radius (km).
  2. Read the result instantly: Escape velocity (km/s).

Frequently asked questions

How does the Escape velocity calculator work?

It takes Mass (×10²⁴ kg) and Radius (km) and derives Escape velocity (km/s) from them. The calculation is live as you type, so the result updates on every change.

Which values does the calculator ask for?

2 values: Mass (×10²⁴ kg) and Radius (km). Nothing else is required — no account, no file upload.

What does a typical calculation look like?

With Mass (×10²⁴ kg) = 5.972 and Radius (km) = 6,371, the calculator returns Escape velocity (km/s) = 11.186. Those figures come from running this exact tool, so you can reproduce them by entering the same values.

How much does the result change with different inputs?

It moves a lot. Using Mass (×10²⁴ kg) = 11.944 and Radius (km) = 7,008 instead, Escape velocity (km/s) goes from 11.186 to 15.083 — which is why it is worth testing a few scenarios rather than trusting a single figure.

What does it give for smaller values?

Scaled down to Mass (×10²⁴ kg) = 2.986 and Radius (km) = 5,734, Escape velocity (km/s) comes out at 8.337. The relationship is worth checking at both ends before you rely on a single result.

When would I actually use this?

Checking a homework answer, sizing something before building it, and getting an order of magnitude before committing to a design — a torque on a bolt, the force a spring returns, the frequency a circuit resonates at, how long light takes to arrive.

What is the most common mistake?

Feeding in a value in the wrong unit. Physics formulas assume SI throughout, so grams instead of kilograms or centimetres instead of metres shifts the answer by powers of ten without any warning.

What is the difference between the Escape velocity calculator and the Orbital velocity calculator?

This one returns Escape velocity (km/s); the Orbital velocity calculator returns Orbital velocity (km/s). That is the whole difference — open the one whose figure you need.

Is there a tool for the next step?

Angular Velocity Calculator is the closest one after this: Convert RPM, rad/s, Hz and period, or derive ω from a linear speed and radius — with tangential speed and centripetal acceleration.

What else is worth having open alongside it?

Velocity Calculator and Centripetal force calculator — they come up in the same task often enough to be worth a second tab.

Further reading

All guides →
GuideThe Four Kinematics Equations: Which One to Use, and What Each One Leaves OutFive variables, four equations, and each equation is missing exactly one of them. Choose by looking at the variable the question never mentions.ExplainerProjectile Motion Explained: Range, Height, Flight Time — and Why 45° Is Not Always BestThree formulas cover the whole of projectile motion on level ground. The catch is level ground: the moment launch and landing heights differ, the 45° result stops being true.ExplainerWhat Is Kinetic Energy? The KE = ½mv² Formula ExplainedKinetic energy is the energy of motion, given by KE = ½mv². Learn what the formula means, why speed matters most, and see worked examples in joules.ExplainerWhat Is Horsepower? Mechanical hp, Metric PS, and kWHorsepower measures the rate of doing work. Learn where the unit came from, how mechanical hp differs from metric PS/CV, and how both relate to kilowatts.ExplainerHow the Doppler Effect Works: The Formula, the Sign Convention, and Why Moving the Source Is Not the Same as Moving the ListenerFor sound, f' = f(v + v_o)/(v − v_s) — and getting the signs backwards is the classic error. Here is the convention spelled out, a 440 Hz source computed at four speeds, and why light needs a different equation entirely.ExplainerWhat Is the Reynolds Number? The Formula, the Units That Cancel, and Why 2 300 Is Only for PipesRe = ρvL/μ compares inertia with viscosity, and the units really do cancel. See the number worked out for honey, a household pipe, an artery, a swimmer and a wing — and why the 2 300 threshold belongs to pipe flow alone.
Escape velocity calculator — OneKitly