Lightweight design is of major priority in innovative mechanical engineering to lower material-costs by improving the component’s performance. Therefore, nowadays new materials (e.g. fiber reinforced composites) and new forming processes are increasingly being employed. Meeting this trend already in the early stages of the design process requires the simultaneous development and implementation of new material models in simulation tools such as finite-element programs. The aim of this thesis is to develop the mathematical framework for a non-destructive surface-strain analysis algorithm involving real 'forming-parts' in order to validate forming processes and material models. In general, the strain state is calculated given the relative displacement of material points. For this purpose a regular reference grid is applied to the forming blank which follows the deformation during the forming process. Subsequently the coordinates of the grid points, which are extracted from the deformed body, are treated as nodes of a finite element. The algorithm can be formulated efficiently in this manner since the strain inside each element can be computed independent from the neighboring elements. The presented mathematical framework allows to adapt the algorithm to individual strain analyses by varying the element type or calculating different strain tensors. Besides a thorough analysis of the algorithm through finite-element simulations a full-field surface-strain analysis has been performed for a real forming part.