thumb|A diagram of Central forces
In classical mechanics, a central force on an object is a force that is directed towards or away from a point called center of force.
<math display="block">\mathbf{F}(\mathbf{r}) = F( \mathbf{r} ) {\hat{\mathbf{r}</math>
where F is a force vector, F is a scalar valued force function (whose absolute value gives the magnitude of the force and is positive if the force is outward and negative if the force is inward), r is the position vector, ||r|| is its length, and <math display="inline"> \hat{\mathbf{r = \mathbf r / \|\mathbf r\|</math> is the corresponding unit vector.
Not all central force fields are conservative or spherically symmetric. However, a central force is conservative if and only if it is spherically symmetric or rotationally invariant.