Same you. Different gravity.

Gravity & escape velocity

Calculate surface gravity, your weight and escape velocity on any world from its mass and radius. Earth: 9.8 m/s² and 11.2 km/s; Mars: 3.7 m/s². With formulas.

Classroom activity Teaching with this lab?

Gravity & escape velocityInteractive model

Surface gravity9.82 m/s²

Your weight687.42 N

Escape speed11.19 km/s

Your experiment

Planet mass Earths

Planet radius Earths

Your mass kg

At 1 Earth masses and 1 Earth radii: weight = 70 kg × 9.82 m/s² = 687.42 N.

How it works

g = GM / R² · weight = mg · vₑ = √(2GM / R)

A planet’s mass increases its pull, while a larger radius puts its surface farther from the center. Your mass stays the same on another world; your weight, a force measured in newtons, changes.

How to Calculate Gravity on Another Planet ↗

About this model
A spherical, non-rotating body without atmospheric drag. Radius means distance from the center to the reference surface. Gas giants do not have a solid surface to stand on.

Key formulas

Quantity	Formula	Note or example
Surface gravity	g = GM / R²	M = mass, R = radius
Scaling from Earth	g ≈ 9.82 m/s² × (M / M⊕) ÷ (R / R⊕)²	Masses and radii in Earth units
Weight	W = m × g	Newtons; your mass m stays the same
Escape velocity	vₑ = √(2GM / R)	Earth ≈ 11.2 km/s

Worked examples

Each row uses one of this lab’s presets and the same model as the interactive tool.

Example	Surface gravity	Your weight	Escape speed
Earth	9.82 m/s²	687.42 N	11.19 km/s
Moon	1.62 m/s²	113.7 N	2.38 km/s
Mars	3.73 m/s²	261.1 N	5.03 km/s

Keep wondering