5 Seconds of Summer, also known as 5SOS, are an Australian pop rock band formed in 2011 in Sydney, Australia. The group consists of lead vocalist Luke Hemmings, lead guitarist Michael Clifford, bassist Calum Hood, and drummer Ashton Irwin. They have released five studio albums and headlined multiple world tours. All singles from their five studio albums, as well as all five albums, have charted in a substantial number of countries, received multiple official sale certifications and have been featured in a large amount of weekly and year-end charts, as well as making an appearance on decade-end charts.