Physics

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Gravitational Force Calculator.

Calculate Newtonian force between two point masses.

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Set your values

Results update as you type.

02 / ANSWER

First mass

Second mass

Separation

Gravitational force

0.000000N

Results update automatically as you type.

Use Cases

Physics homework and learning

Verify your manual calculations of gravitational force between two masses, such as in textbook problems or lab exercises.

Example: Calculate the force between Earth (5.97e24 kg) and a 1000 kg satellite at 6.37e6 m separation.

Astronomy and space mission planning

Estimate gravitational interactions between celestial bodies or spacecraft and planets for mission design and orbital mechanics.

Example: Find the force between the Moon (7.35e22 kg) and a 500 kg probe at 1.74e6 m separation.

Frequently Asked Questions

What is the gravitational force calculator?: It calculates the attractive force between two point masses using Newton's law of universal gravitation: F = G * m1 * m2 / r^2. You input the first mass (kg), second mass (kg), and separation (m), and it outputs the force in newtons.
What units does the calculator use?: Masses are entered in kilograms (kg) and separation in meters (m). The resulting force is given in newtons (N).
Can I use this for objects like planets or apples?: Yes, it works for any two point masses, but for everyday objects the force is extremely small. For large masses like planets, the force becomes significant.

Tips & Common Mistakes

Tips

Ensure masses are in kilograms and separation in meters to get the force in newtons.
For very small masses, the force will be tiny; use scientific notation for clarity.
Remember that the force is always attractive, pulling the two masses toward each other.
Double-check your separation: it's the distance between the centers of the two masses.

Common Mistakes to Avoid

Using grams or kilometers without converting to kg and meters, leading to incorrect force values.
Forgetting to square the separation distance in the denominator.
Confusing the gravitational constant G (6.674e-11 N·m²/kg²) with other constants.

Last updated: August 13, 2026

Use Cases

Physics homework and learning

Verify your manual calculations of gravitational force between two masses, such as in textbook problems or lab exercises.

Example: Calculate the force between Earth (5.97e24 kg) and a 1000 kg satellite at 6.37e6 m separation.

Astronomy and space mission planning

Estimate gravitational interactions between celestial bodies or spacecraft and planets for mission design and orbital mechanics.

Example: Find the force between the Moon (7.35e22 kg) and a 500 kg probe at 1.74e6 m separation.

Frequently Asked Questions

What is the gravitational force calculator?

It calculates the attractive force between two point masses using Newton's law of universal gravitation: F = G * m1 * m2 / r^2. You input the first mass (kg), second mass (kg), and separation (m), and it outputs the force in newtons.

What units does the calculator use?

Masses are entered in kilograms (kg) and separation in meters (m). The resulting force is given in newtons (N).

Can I use this for objects like planets or apples?

Yes, it works for any two point masses, but for everyday objects the force is extremely small. For large masses like planets, the force becomes significant.

Tips & Common Mistakes

Tips

Ensure masses are in kilograms and separation in meters to get the force in newtons.
For very small masses, the force will be tiny; use scientific notation for clarity.
Remember that the force is always attractive, pulling the two masses toward each other.
Double-check your separation: it's the distance between the centers of the two masses.

Common Mistakes to Avoid

Using grams or kilometers without converting to kg and meters, leading to incorrect force values.
Forgetting to square the separation distance in the denominator.
Confusing the gravitational constant G (6.674e-11 N·m²/kg²) with other constants.

Use Cases

Physics homework and learning

Verify your manual calculations of gravitational force between two masses, such as in textbook problems or lab exercises.

Example: Calculate the force between Earth (5.97e24 kg) and a 1000 kg satellite at 6.37e6 m separation.

Astronomy and space mission planning

Estimate gravitational interactions between celestial bodies or spacecraft and planets for mission design and orbital mechanics.

Example: Find the force between the Moon (7.35e22 kg) and a 500 kg probe at 1.74e6 m separation.

Frequently Asked Questions

What is the gravitational force calculator?

What units does the calculator use?

Masses are entered in kilograms (kg) and separation in meters (m). The resulting force is given in newtons (N).

Can I use this for objects like planets or apples?

Yes, it works for any two point masses, but for everyday objects the force is extremely small. For large masses like planets, the force becomes significant.

Tips & Common Mistakes

Tips

Ensure masses are in kilograms and separation in meters to get the force in newtons.
For very small masses, the force will be tiny; use scientific notation for clarity.
Remember that the force is always attractive, pulling the two masses toward each other.
Double-check your separation: it's the distance between the centers of the two masses.

Common Mistakes to Avoid

Using grams or kilometers without converting to kg and meters, leading to incorrect force values.
Forgetting to square the separation distance in the denominator.
Confusing the gravitational constant G (6.674e-11 N·m²/kg²) with other constants.