Madhouse produced a twenty-six episode anime series based on the manga series. Directed by Hiroyuki Tanaka, the series aired between April 2007 and September 2007 in Japan on Nippon Television. The series adapts the first eleven volumes of its source material over the first 24 episodes, then uses an alternate ending for its final two episodes. It is speculated by many that this is the probable reason for the lack of a second season.
As of February 2008, seven DVD volumes, each containing three episodes of the anime, have been released in Japan by Avex Trax. In addition, four limited edition sets have been released. The first limited edition set contains the first DVD volume, while the other three sets each contain two DVD volumes. The latest limited edition set and volumes were released on January 30, 2008. Two more DVD volumes and one more limited edition set are planned for release on March 26, 2008. On February 15, 2008, Funimation announced that it has acquired the Region 1 DVD and broadcast licenses for the anime, and released the first DVD in North America on October 14, 2008: as of February 2009, three volumes have been released. On February 16, 2010, Funimation released a boxed set containing the complete series in Blu-ray format. Madman Entertainment has licensed the series and Volume 1 released early 2009.
The series made its North American television debut when it started airing on the FUNimation Channel September 6, 2010. Netflix also made Claymore available for streaming, but the series has been removed as of April 2012. All 26 episodes are available on Hulu, however, and Funimation via their streaming video service and DVD.