Exam Owl is your one stop destination for testing help. Featuring AP, IB, SAT, ACT and Final Grade/GPA calculators, forums and resources.
Began as a personal project to help out my fellow students in 2014 and has grown to become the world's second most popular AP score site.
Boasts the only up-to-date scoring formulas as of April, 2016 and features a responsive mobile design.
Built from scratch with PHP and a custom MVC framework.