About the Friction Calculator
Friction force from the normal force and coefficient of friction, on the flat or on a slope.
Also known as: friction force, coefficient of friction, normal force calculator.
How to use this calculator
- Enter mass, coefficient of friction, surface angle, applied force (optional).
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
f = μ × N, N = mg·cos θ
Worked example
Using the values pre-filled in the calculator above:
- Mass = 50 kg
- Coefficient of friction = 0.35
- Surface angle = 0 °
- Applied force (optional) = 0 N
the calculator returns:
- Friction force: 171.62 N
- Normal force: 490.33 N
- Gravity component along slope: 0 N
- Net force: -171.62 N