Add to ORKGManipulability ellipsoids and polytopes are well-known tools to graphically represents these capabilities. This paper focuses on the evaluation of force capabilities for redundant manipulators, for which additional constraints must be imposed on the available joint torques in order to satisfy the static assumption. An algorithm to correctly evaluate the task space force polytope is given and a new definition of the force ellipsoid is proposed. The obtained results can be applied also to nonredundant manipulators in singular configurations. Numerical results are provided in the case of a planar redundant arm