Usually, it is considered to be around 15% to 25% of the total project cost. However, a variety of factors may influence the final cost of the testing process. For example, if you are getting the product built from scratch involving skilled developers, then you may require one tester for every 5-6 developers. However, if you want to get an existing software or app tested, then the number of testers may vary depending on the complexity of the product. It's advisable to consult one of our associates for proper estimates.