This calculator finds the gravitational force between any two objects using Newton's law of universal gravitation. Enter the two masses and the distance between their centres, and it returns the attractive force in newtons and other units. The gravitational constant G is filled in automatically.
What the symbols mean
- F — gravitational force (newtons).
- G — gravitational constant, 6.674×10⁻¹¹ N·m²·kg⁻² (auto-filled).
- m₁, m₂ — the two masses (kilograms).
- r — distance between the centres of the masses (metres).
Worked example
For the Earth (5.97×10²⁴ kg) and the Moon (7.34×10²² kg) separated by 3.84×10⁸ m, the force is about 1.98×10²⁰ N — the pull that keeps the Moon in orbit.
Want the full story behind this formula? Read our guide: Gravitational Force.