Johnny Test is a Canadian animated television series. It premiered on Kids' WB, on The WB Television Network, on September 17, 2005. The series currently airs in the United States on Cartoon Network, as of January 7, 2008, and in Canada on Teletoon, as of October 28, 2006. The show was produced by Cookie Jar Entertainment for its second and later seasons. The series is rated TV-Y7 for the first four seasons, and TV-Y7-FV for the fifth. The sixth season of Johnny Test was ordered in the early March season. It began airing on April 3, 2013, starting with the episode "Johnny on the Clock" on Cartoon Network in the United States. This season will feature its 100th episode, making it the first Teletoon series and the fourth Cartoon Network to pass the 100-episode milestone. According to creator Scott Fellows, the 100th episode will be a half-hour special. This season is the first to broadcast in high-definition on Cartoon Network in the United States. This season also features the re-appearance of Ashleigh Ball, who departed from the show after the fourth season, due to working on other projects.