Gravitational Force Calculator

F = G × m₁ × m₂ ÷ r²
Mass must be greater than 0.
Mass must be greater than 0.
Distance must be greater than 0.
Custom G must be greater than 0.
Quick summary
Enter m₁, m₂, and r, then click Calculate.

Results

Force
N
Force
lbf
Acceleration on m₂
m/s²
Acceleration on m₁
m/s²
All calculations are performed in SI units first.

Use this Gravitational Force Calculator to find the attractive force between two masses from their masses and center-to-center separation distance.

Calculation Method

Newton’s law of universal gravitation is:

F = G × m₁ × m₂ ÷ r²

Where:

  • F = gravitational force in newtons
  • m₁ and m₂ = masses in kilograms
  • r = center-to-center distance in meters
  • G = 6.67430 × 10−11 N·m²/kg²

The acceleration of either mass can also be calculated with:

a = F ÷ m

Example

For two 1 kg masses separated by 1 meter:

F = 6.67430 × 10−11 × 1 × 1 ÷ 1²

F = 6.67430 × 10−11 N

Important Note

The formula directly applies to point masses and works for spherically symmetric objects when the distance is measured between their centers. More complex mass distributions or strong-gravity systems may require more advanced models.

Sources

More of our calculators...

Potential Energy Calculator

Use our Potential Energy Calculator to find gravitational or elastic potential energy using mgh or ½kx². Get instant results in J, kJ, Wh, kWh, and ft·lbf.

Velocity Calculator

Use our Velocity Calculator to find average velocity from distance or displacement and time. Get instant results in m/s, km/h, mph, and ft/s.

Projectile Motion Calculator

Use our Projectile Motion Calculator to find time of flight, range, maximum height, time to peak, and velocity components from speed, angle, height, and gravity.

Kinetic Energy Calculator

Use our Kinetic Energy Calculator to find KE from mass and velocity. Get instant results in joules, kJ, Wh, kWh, and ft·lbf with unit conversion.

Work and Power Calculator

Use our Work and Power Calculator to find work from force and distance or lift, then calculate power in watts, kW, and horsepower from time.

Free Fall Calculator

Use our Free Fall Calculator to find time, distance, final velocity, and average speed from height or time with gravity presets and unit conversion.

Pressure Calculator

Use our Pressure Calculator to find pressure from force and area. Get instant results in Pa, kPa, bar, psi, and atm with built-in unit conversion.

Wavelength → Frequency Calculator

Use our Wavelength to Frequency Calculator to find frequency from wavelength with vacuum, air, water, or custom wave speed. Fast SI-based results online.

Ohm’s Law Resistance Calculator

Use our Ohm’s Law Resistance Calculator to find resistance from voltage and current. Get instant results in Ω, kΩ, or MΩ plus power and conductance.