What is gravitational field strength?

Gravitational field strength (g) is the gravitational force experienced per unit mass at a point in space, measured in m/s² (or equivalently N/kg). At Earth's surface it is approximately 9.81 m/s².

What formula does this calculator use?

The calculator uses Newton's law of universal gravitation: g = GM/r², where G = 6.674 × 10⁻¹¹ N·m²/kg², M is the mass of the body in kg, and r is the distance from its center in meters.

How does distance affect gravitational field strength?

Gravitational field strength follows an inverse-square law: doubling the distance reduces g to one quarter of its original value. At twice the Earth's radius, surface gravity drops to about 2.45 m/s².

Why is g different on different planets?

Each planet has a different mass and radius. Larger mass increases g, while larger radius decreases it. Jupiter's enormous mass gives it a surface gravity of about 24.8 m/s², while Mars's smaller mass yields only 3.73 m/s².

What is the difference between g and G?

G (capital) is the universal gravitational constant, 6.674 × 10⁻¹¹ N·m²/kg², a fixed number of nature. g (lowercase) is the local gravitational field strength, which varies with location and the body you are near.

Can I use this for orbit calculations?

Yes. Enter the planet's mass and set the distance to the orbital radius (planet radius + altitude). The result is the gravitational acceleration experienced by an orbiting satellite at that altitude.

Gravitational Field Strength Calculator

Name: Gravitational Field Strength Calculator
Availability: InStock
Author: Nham Vu

Calculate the gravitational field strength at any distance from a planet or star using g = GM/r².

Inputs

Celestial Body Preset

Mass of Body (kg) e.g. 5.972e24

Distance from Center (m) e.g. 6.371e6

Formula: g = GM / r² · G = 6.674 × 10⁻¹¹ N·m²/kg²

Select a preset or enter values to calculate gravitational field strength.

Surface Gravity Comparison

Body	g (m/s²)	vs Earth

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