Calculadora de Gravidade na Superfície de Planetas
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
Formula
g = G·M/r²
About this calculator
This calculator determines the surface gravity of planets in the Solar System using the formula g = G × M / r², where G is the gravitational constant (6.67430×10⁻¹¹ m³ kg⁻¹ s⁻²), M is the planet's mass, and r is its radius. Simply select a planet or manually input mass and radius to get g in m/s².
The calculation helps compare an object's weight on different worlds: weight equals mass times local gravity. For example, Earth's g ≈ 9.8 m/s², Mars ≈ 3.7 m/s², Jupiter ≈ 24.8 m/s². You can also use it for moons, asteroids, or exoplanets by providing mass and radius.
Note: the formula assumes a spherical, homogeneous planet, which is an approximation. Non-spherical bodies or uneven mass distribution may cause local variations. Also, planetary rotation slightly reduces effective gravity at the equator, an effect not included here. Use for educational and comparative purposes.
Frequently asked questions
What is the surface gravity of the Moon?
The Moon's surface gravity is about 1.62 m/s², roughly 1/6 of Earth's. An object weighing 60 kg on Earth would weigh about 10 kg on the Moon.
Why is Jupiter's gravity so high?
Jupiter has an enormous mass (about 318 times Earth's), which increases gravitational pull. Despite its large radius, the mass concentration results in a surface gravity of about 24.8 m/s².
Does gravity vary with altitude on a planet?
Yes, gravity decreases as altitude increases because the distance from the planet's center grows. The formula uses the mean radius, so at high altitudes the actual value is lower.
Can I use this calculator for exoplanets?
Yes, select the 'Custom' option and enter the exoplanet's mass and radius. Make sure to use consistent units (kg and meters) to get the correct result.
Does planetary rotation affect gravity?
Yes, rotation produces a centrifugal force that reduces effective gravity, especially at the equator. This calculator does not account for that effect, providing the theoretical non-rotating gravity.