The lateral profile of the injection current along the active layer in multiple stripe laser diodes is analyzed for the practical case of homogeneous current density within each individual stripe contact. By means of conformal mapping an exact analytical solution is found for arbitrary contact configurations (number, width, and location) driven with different currents. The simple form of the solution eases the analysis of modal gain and supermode discrimination in gain‐guided and index‐guided arrays of stripe‐geometry laser diodes.