Power transformer losses are important to estimate and measure both for producers and for utilities. The question becomes even more critical when the power transformer is carrying load currents with harmonics. It is important to be able to calculate the load losses accurately in order to be able to estimate hot spot temperatures and total losses during operation. Finite Element methods are well known and well proven during the last 40 years. Producers usually have proprietary programs that are developed and used in house. These programs are restricted and are not available for academic research. In this paper, a parametric model of a power transformer is made in COMSOL so that important dimensions of transformers can be entered to yield realistic loss calculations.