The invention embodies a system for analyzing and guiding optimum fit implant for knee replacement (S) mainly comprises of: User Input Element (UE), Computational Element (CE), Information Display Element (DE) and Storage Element (SE). It reads a CT scan and creates a 3D model on which the surgeon picks landmarks. Based on these and surgeon™s preferences, it auto-selects a first implant. It allows virtual manipulation of said first implant by a surgeon (user) to achieve optimum fit implant for given bone. In addition, values with respect to size and depth of cuts, different angles and bone loss are calculated. It allows selection of other implants and allows its manipulations with visualization for obtaining an optimum fit implant. It allows comparison of different implants and their position and alignments. The present system (S) facilitates the clinical decisions of surgeon for planning knee replacement surgery with minimum bone loss and maximum recovery. Fig. 1
