A function reader is a program that can read an input function and evaluate the function for a given input value at run time. Any Computer Algebra System and Graphing Calculator are function readers. Evaluation of a given function is often done by using a function reader. However, any Computer Algebra System or Graphing Calculator is costly. As the world is connected by the Internet, would that be nice if we can evaluate a given function by using an online function reader? In this paper, we demonstrate a strategy with actual source code of implementing such a program online that can be used by any individual as well as any group such as a class of mathematics. Key words: function reader, online.