The ability of trailing edge serrations to reduce turbulent boundary layer trailing edge noise is examined through numerical optimization studies. The in-house optimization program, SAGRGSTEN, is developed and implemented. Two different serration geometries are optimized for both, the overall noise (from 20 Hz to 20 kHz), and the noise produced at individual frequencies throughout the same range. The noise was modeled using Howe’s semi-empirical model for a semi-infinite flat plate, at zero angle of attack to the mean, low Mach number, flow. Results of the optimization studies are used to investigate the influence of serration design parameters. It is shown that the multi-tooth-size serrated trailing edges yield greater noise reductions than single-size serrated trailing edges. Based on this finding, a novel design is proposed for a multi-tooth-size sawtooth serrated TE profile. It is also shown that, based on the bounds used, the serration design that yields the greatest amount of total noise reduction is a multi-tooth-size slitted trailing edge.