An energy beam profiler and calorimeter (EPC) is disclosed. The EPC includes a target board having a front surface and a back surface, a first plurality of oscillating heat pipes arranged as columns on a first plate, and a second plurality of oscillating heat pipes arranged as rows on a second plate. The target board is configured to receive an impinging energy beam at the front surface of the target board, and the first plate and second plate are adjacent to and in thermal communication with the back surface of the target board.