Friction Calculator

Enter the coefficient of friction and the normal force between two objects to calculate the force due to friction. This calculator is for static or kinetic friction, just make sure you use the correct coefficients.


Friction is a force between two objects that resists motion. It’s a factor of both normal force, the force between two objects, and the roughness of their surfaces.

Friction Formula :

Force of Friction (F) = U * N

Where U is an empirical measurement of the two contacting properties and N is the normal force between the two objects. The normal force acts perpendicular to the surfaces.

The coefficient of friction is the key scalar quantity in this formula, and the science behind how it’s measured is quite interesting. This coefficient depends on material deformation characteristics, surface roughness, and chemical bonding between atoms in the materials.

Another factor that influences the coefficient of friction is the fractality of it, which is a parameter that looks at the surfaces asperities. This subject is a little beyond our expertise, and we will leave that to further research if you are interested.

Friction Calculator

The coefficient of friction ranges from just above 0 to above 1 for very “sticky” materials. For must dry materials, this value is between .3-.6. A value of 0 is impossible to achieve because that means there would be no friction at all, which is not something that scientists have found in nature yet.

This value also relies on variable like temperature, velocity, and atmosphere, along with many others.

For more information, visit our science and engineering calculators.