Wikipedia
PCGen
PCGen is a character creation and role-playing game playing aid program for d20 System-based games, such as Dungeons & Dragons.
The software is written in Java and runs on any system that supports Java 1.6 or later.
The program has won ENnies ( EN World awards) at Gen Con twice; a bronze in 2003 for Best Resource/Fan Site and a gold in 2005 for Best Electronic Product.