Approximate computing, also called imprecise or inaccurate computing, is a potential alternative to conventional accurate computing due to its ability to improve the speed, reduce the chip area, minimize the power consumption and optimize the energy required by the design, while providing acceptably correct computation results. In practical applications such as Image Processing, low power graphics processing, multimedia, big data analytics, artificial intelligence and machine learning, neuro morphic computing etc. Combinational Modules have the advantage to interface the design with some appliactions like image processing. Here the N-bit Approximate comparator is implemented by taking reference of N as 2-bit, 4-bit and 8-bit. The design analyzes the fractional change in Error to Bit in several bit formats. Final implementation of Approximate design compares the Structural Similarity Index (SSIM), Colour and extraction of an image to the results.The computations, evaluation of errors and the Applications were executed using Python.