This research investigates five-axis end milling force prediction and feedrate selection using integrated geometric and mechanistic models. A discretized tool envelope is used to determine the contact area between the cutting tool and the workpiece for each tool move during five-axis milling. This discrete method uses a three-axis approximation of the tool movement envelope to find the contact area. A discrete end mill mechanistic model is then used to calculate the optimum feedrate for that tool movement based on the contact area.