Tailored blanks are essential elements of state of the art vehicles in the automotive industries due to their ability of fitting distinct approvals like light weight construction, crash safety, reduction of material consumption, environmental awareness or cost efficiency. Issue of this paper is to characterise different laser welded tailored blanks by means of the hydraulic bulge test. The investigations where recorded by the stereo-optical 3D-measurement-system ARAMIS and analysed using an Excel VBA-code for processing the data afterwards. The results are stated to be flow curves and reachable deep drawing depths of different tailored blanks in a range of thicknesses from 0,7 mm to 2,5 mm and ultimate tensile strengths from 260 MPa up to 780 MPa, as well as the deviations of the seams which may be predicted by an approximation equation.