Luke Robert Hemmings is an Australian singer and songwriter, best known as the singer and rhythm guitarist of the Australian band 5 Seconds of Summer. Since 2014, 5 Seconds of Summer has sold over 10 million albums, sold over 2 million concert tickets worldwide, and the group's number of songs has exceeded 7 billion, making it one of the most successful Australian music exports in history.

He is the guitarist and main vocalist for the Australian rock band 5 Seconds of Summer. Their debut single,"She Looks So Perfect", topped the charts in Australia, New Zealand, Ireland, and the United Kingdom. Their self-titled debut album debuted at number one in 11 countries.