Magnetic Resonance Imaging (MRI) is a medical imaging technique used for analyzing and diagnosing diseases such as cancer or tumor in a brain. In order to analyze these diseases, physicians require good contrast scanned images obtained from MRI for better treatment purpose as it contains maximum information of the disease. MRI images are low-contrast images which lead to difficulty in diagnoses, hence better localization of image pixels is required. Histogram equalization techniques help to enhance the image so that it gives an improved visual quality and a well-defined problem. The contrast and brightness are enhanced in such a way that it does not lose its original information and the brightness is preserved. In this paper, we compared the different equalization techniques which are critically studied and elaborated. Various parameters are calculated and tabulated, finally concluded the best among them. © 2020, Springer Nature Singapore Pte Ltd.