Sum 41 is a Canadian rock band from Ajax, Ontario, active since 1996. The current members are Deryck Whibley (lead vocals, rhythm guitar), Jason McCaslin (bass guitar, backing vocals), Steve Jocz (drums, backing vocals), and Tom Thacker (lead guitar, backing vocals, keyboard).
In 1999, the band signed an international record deal with Island Records. Since then, the band has released four studio albums, all of which have been certified platinum in Canada. Their most successful album to date is All Killer No Filler, which is certified 1x platinum in Canada and platinum in the United States.