B'z (Japanese: ビーズ, Hepburn: Bīzu) are a Japanese rock duo, consisting of guitarist, composer and producer Takahiro "Tak" Matsumoto (松本 孝弘, Matsumoto Takahiro) and vocalist and lyricist Koshi Inaba (稲葉 浩志, Inaba Kōshi), known for their energetic hard rock tracks and pop rock ballads. B'z is one of the best-selling music artists in the world and the best-selling in their native Japan, having released 49 consecutive No. 1 singles, 25 No. 1 albums, 3 No. 1 EPs on the Oricon music charts and sold more than 100 million records worldwide.
In 2003 HMV Japan ranked them at number 30 on their list of the 100 most important Japanese pop acts. In 2007, B'z became the first music act from Asia to have their handprints and signatures put up in the Hollywood's RockWalk. In 2008 were awarded a Guinness World Record for "Best selling album act in Japan", which also notes them to be the best selling act in Japan overall. By AllMusic are considered as the "biggest rock act in Japan and the entirety of Asia".