Enter the mass of two objects and the distance between them to calculate the gravitational force acting between them. Plug in Mass 1 (m1), Mass 2 (m2), and Distance (r) — your result shows the attractive force in Newtons (N) using Newton's law of universal gravitation (F = G × m1 × m2 / r²).
Gravitational Force (F)
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Force (Scientific Notation)
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Gravitational Constant (G)
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Acceleration on Object 1 (F/m1)
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Acceleration on Object 2 (F/m2)
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Gravitational force is the mutual attractive force between any two objects that have mass. According to Newton's law of universal gravitation, every object with mass attracts every other object in the universe. The strength of this force depends on the masses of both objects and the distance between them.
The gravitational force formula is F = G × (m1 × m2) / r², where F is the gravitational force in Newtons, G is the gravitational constant (6.674 × 10⁻¹¹ N·m²/kg²), m1 and m2 are the masses of the two objects in kilograms, and r is the center-to-center distance between them in meters.
The universal gravitational constant G is approximately 6.674 × 10⁻¹¹ N·m²/kg² (or m³·kg⁻¹·s⁻²). It is a fundamental physical constant that appears in Newton's law of universal gravitation and was first measured by Henry Cavendish in 1798.
To calculate gravitational force: (1) Identify the masses of both objects in kg. (2) Measure or look up the distance between their centers in meters. (3) Plug into F = G × m1 × m2 / r², using G = 6.674 × 10⁻¹¹. (4) The result is the force in Newtons — it acts equally on both objects in opposite directions.
Using Earth's mass (5.972 × 10²⁴ kg), the Moon's mass (7.342 × 10²² kg), and the average Earth–Moon distance (3.844 × 10⁸ m), the gravitational force is approximately 1.98 × 10²⁰ Newtons. This enormous force keeps the Moon in orbit around Earth.
Because gravitational force is inversely proportional to the square of the distance (r²), doubling the distance reduces the force to one-quarter (1/4) of its original value. This is known as an inverse-square law. Halving the distance, conversely, would quadruple the force.
Technically yes — every object with mass exerts gravitational pull on every other object. However, the gravitational force exerted by distant planets on a human body is extraordinarily tiny — far smaller than the gravitational pull of nearby everyday objects like buildings or cars. It has no measurable physical effect on humans.
Not exactly — 9.8 m/s² (often rounded to 9.81 m/s²) is the standard average surface gravitational acceleration. In reality it varies slightly by location due to Earth's non-uniform density, rotation, and shape. At the poles it is slightly stronger (~9.83 m/s²) and at the equator slightly weaker (~9.78 m/s²).