Gravitational Force Calculator

Apply Newton's law of universal gravitation to two masses and the distance between them.

Newton's law of universal gravitation

Mass 1 (kg) Mass 2 (kg)

Distance between centres (m)

Result: —

Scientific: —

Surface gravity ratio: —

The constant G is 6.67430e-11 N m2 / kg2, so force falls with the square of the distance.

Common questions about the free online gravitational force calculator.

Multiply the two masses and the gravitational constant, then divide by the square of the distance between their centres.

Every mass attracts every other mass with a force proportional to both masses and inversely proportional to the square of their separation.

G is about 6.67430 times ten to the minus eleven newton square metres per kilogram squared, a very small number.

Because G is extremely small, so two ordinary masses attract each other with a force far too tiny to notice.

Force equals G times mass one times mass two divided by the square of the distance, written as F = G m1 m2 / r squared.

The force falls to one quarter of its original value, because the distance is squared in the denominator of the law.

For a 1000 kilogram object at the Earth surface the attraction is about 9810 newtons, giving an acceleration of 9.81 metres per second squared.

Gravitational force is always attractive, so the magnitude alone is normally reported and the sign is not needed.

No. The calculation runs entirely in your browser, so the masses and distances you enter stay on your own device.

Yes. It is completely free and unlimited, with no account, no sign-up, no paywall and no usage limits at all.

Last updated: October 10, 2026