John W. Ratcliff (born 1961) is an American video game programmer and designer best known for creating 688 Attack Sub and SSN-21 Seawolf.
Together with John A. Obershelp in 1988 he developed the Ratcliff/Obershelp pattern-matching algorithm also known as Gestalt Pattern Matching to improve educational software.
His most recent released title was as lead engine programmer for PlanetSide, published by Sony Online Entertainment.
Ratcliff continues to be an active member of the game development community and has been a contributing author to such magazines as Dr. Dobb's Journal.
In 2006, he worked for AGEIA, where his role was to provide open source tools and technology to facilitate the integration of physics into games.