# Friction Calculator

> Calculate friction force from a coefficient of friction and normal force or mass.

Page: https://askcalculators.com/calculator/friction-calculator/
Definition: https://askcalculators.com/calculator/friction-calculator/definition.json
JSON Schema: https://askcalculators.com/calculator/friction-calculator/schema.json
Version: 1.0.0
Maintained by: AskCalculators (software project; not a credentialed reviewer)
Qualified review: pending. Automated checks do not establish professional approval.
Page status: Live
Review status: Pending

## Use
Open the calculator page and enter values. Query-string parameters can restore and bookmark a calculation.
Example: https://askcalculators.com/calculator/friction-calculator/?normalSource=mass&coefficient=0.3&mass=20&gravity=9.80665&normalForce=196.133

## Inputs
- normalSource: Normal force input; type=select; required; default=mass; values=mass|normal
- coefficient: Coefficient of friction μ; type=number; required; default=0.3; min=0
- mass: Mass (kg); type=number; required; default=20; min=0
- gravity: Gravity (m/s²); type=number; required; default=9.80665; min=0.000001
- normalForce: Normal force (N); type=number; required; default=196.133; min=0

## Outputs
- frictionForce: Friction force (N); format=number; primary
- normalForceResult: Normal force used (N); format=number

## Formula
friction force f = μN; on a level surface N = mg

## Rules
- Empty optional inputs are undefined, not zero.
- Hidden conditional inputs are ignored.
- Do not invent missing required inputs.