A laser-welded blank (LWB) offers several notable benefits including decreased part weight, reduced manufacturing costs, increased environmental friendliness and improved dimensional consistency. However, in order to take advantage of these benefits, designers need to overcome the formability of LWBs and be able to accurately predict the LWB forming characteristics early in the design process. We present a new approach to predict the maximum elongation of the laser seam; for example, for Advanced High-Strength Steel (AHSS)-based LWBs. This approach is based on a coupling model taking into account the thermal, metallurgical and mechanical phenomena. A comparison of numerical and experimental results shows very good agreement. These approaches offer a considerable advantage in obtaining the formability limits for all configurations.