||Antioxidant properties have been credited to medicinal plants because plants have to counteract themselves from stress caused by oxygen. Plants have no side effects and provide protection against free radicals, thus prevent our body from oxidative damage. As a result, it is very much necessary to screen medicinal plants for their antioxidant properties. There are several in vitro assays are reported for measurement of antioxidant properties. Results comparability is largely dependent on the techniques employed in the investigations and conclusive results can only be obtained if methods are standardized and worldwide. In the light of the fact, the present review is designed for the simplicity and feasibility of the authors to use the appropriate methods based on the availability of the instruments, so as to reduce the time consumption. This review offers an idea behind the mechanism involved in each test assay. At the same time it also provide information on the most common methods used in the present day to study antioxidant activity with their advantages and comparison of different standards used by several authors.