Increased interest in battery-powered hydraulic quadrupeds at the US Naval Research Laboratory has created demand for compact hydraulic power units with electric prime movers. Brushless DC (BLDC) motors are compact, high-power systems that can provide the shaft power for a hydraulic pump. The remote-control hobby industry offers a wide range of low-cost BLDC motors that can be utilized for miniature, power-dense hydraulic powertrains. However, most of these motors are sold with minimal specifications that prevent accurate prediction of the motor performance, impeding precise motor selection. An analytical model has been developed to provide an upper bound on a motor’s performance based on the motor constant and the motor phase impedance. Experimental performance of multiple motors are used to validate the model and demonstrate its efficacy for motor selection.