A performance prediction model software was developed to predict the performance of a particular configuration of an active sonar by computing transmission loss, reverberation levels and the signal excess, using various environmental inputs such as wind speed, ambient noise sound speed profile, type of the bottom etc. This model assumes a vertical transmission system, horizontal receive system and a flat sea bottom. This model uses the complete transmit and receive beam pattern in reverberation calculation. It is a 2D model and assumes a mono-static geometry. This model is based on Ray theory and uses Bellhop transmission loss model, developed by NATO-SCLANT, for transmission loss calculation. This software has an extremely user friendly MATLAB GUI that is portable on many operating systems such UNIX, LINUX, WINDOW etc.