Paul Kevin Jonas (II) Nickname: K2 (born November 5, 1987) - Lead guitar (usually a Gibson Les Paul) and backing vocals. The eldest of the band, goes by Kevin rather than Paul. Kevin helped produce the band's self-titled CD Jonas Brothers.
Joseph Adam Jonas Nickname: DJ Danger (born August 15, 1989) - Lead vocals, percussion, guitar (in the songs "Please Be Mine", "A Little Bit Longer", and "Love is on it's way") and keyboard in the song "Year 3000" and "Hold On". Joe originally had no intention of becoming a singer; he wanted to be a comedian and work on the show All That.
Nicholas Jerry Jonas Nickname: Mr.President (born September 16, 1992) - Lead vocals, rhythm guitar (usually a Gibson SG in the original red stain color), piano in the songs "When You Look Me in the Eyes", "A Little Bit Longer, and "Love is on its way" and drums in the songs "Australia", Can't Have You", "Sorry","Video Girl", and "On the Line" by Demi Lovato. Nick is the youngest brother in the band. On November 16, 2005 he was diagnosed with type 1 diabetes.
Franklin Nathaniel Jonasa (born September 28, 2000), also known as the "Bonus Jonas" and "Frank the Tank." He will debut with his brothers on J.O.N.A.S!, and might have a small appearance in Camp Rock 2. He will also play the voice of "Sosuke" in the English-dubbed version of Hayao Miyazaki's animated film Ponyo on the Cliff by the Sea.