This document discusses the contact stress analysis of spur gears using finite element analysis. It begins by introducing pitting and Hertzian contact stresses in gears. It then discusses modeling spur gears in SolidWorks and analyzing the contact stresses using ANSYS. The analytical and ANSYS results both show that contact pressure decreases with increasing gear module. The conclusions drawn are that a higher module gear is better for transmitting large power and has a higher safety factor. Future work could look at applying gear coatings to reduce contact stresses.