Gravitational Force Calculator
Newton's law of universal gravitation.
Enter your values
Enter the mass 1 in kg.
Enter the mass 2 in kg.
Enter the distance in km.
Results update instantly as you type — no submit needed. Your values are remembered on this device, and the shareable link reopens the calculator with exactly these numbers.
- Gravitational force
- 1.9821e+20 N
- Acceleration of mass 2
- 2.6975e-3 m/s²
- Distance
- 384400 km
- Force in tonnes-force
- 2.021e+16
Quick answer
Gravitational force falls with the square of the distance between two masses.
F = G m1 m2 ÷ r²
At a glance
| What it does | Newton's law of universal gravitation. |
|---|---|
| Category | Science |
| Inputs needed | Mass 1, Mass 2, Distance |
| Main output | Gravitational force |
| Formula | F = G m1 m2 ÷ r² |
| Cost | Free — no sign-up, no download |
How to use the Gravitational Force Calculator
- 1Enter both masses in kilograms.
- 2Enter the separation between their centres.
- 3Read the resulting force.
Inputs explained
- Mass 1(kg)
- Enter the mass 1 in kg.
- Mass 2(kg)
- Enter the mass 2 in kg.
- Distance(km)
- Enter the distance in km.
Worked example
Using the values the calculator loads with:
Inputs
- Mass 15.972e24 kg
- Mass 27.348e22 kg
- Distance384400 km
Results
- Gravitational force1.9821e+20 N
- Acceleration of mass 22.6975e-3 m/s²
- Distance384400 km
- Force in tonnes-force2.021e+16
Frequently asked questions
Why is gravity so weak?
G is tiny, so noticeable gravity needs planetary-scale mass.
Does distance or mass matter more?
Distance — the inverse square makes separation dominate.
What do I need to enter into the Gravitational Force Calculator?
Just 3 values: mass 1, mass 2, distance. Every field starts with a realistic example, so you can change one number at a time and watch the result update instantly.
How does the Gravitational Force Calculator work out the answer?
Gravitational force falls with the square of the distance between two masses. It applies the formula F = G m1 m2 ÷ r² and shows the working so you can check each step by hand.
Is the Gravitational Force Calculator free, and do I need an account?
It is completely free with no sign-up, no download and no usage limit. Everything is calculated in your browser, so the numbers you type never leave your device.
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.