A simple computational model was devised to predict the results of forward masking experiments which use tonal probes and maskers. Using straight‐line approximations for the hypothetical underlying excitation patterns and a fixed “detection” criterion, the model predicts “masked threshold” for a given combination of masker and probe parameters. Discussion will center upon the validity of the simplifying assumptions and the comparisons between predicted and observed values. [Work supported by a David Ross Fellowship from Purdue University and grants from N.I.H.]