In late 2011, Irwin received a
Facebook message from friend and future band-mate,
Michael Clifford, asking if Irwin was interested in casually playing music with him,
Calum Hood and
Luke Hemmings. Irwin agreed, eventually joining the trio in posting song covers on Hemmings'
YouTube channel, and forming the
5 Seconds of Summer lineup. After months of posting song covers together, the band began attracting interest from major music labels and publishers and signed a publishing deal with
Sony/ATV Music Publishing. Irwin has since released six studio albums with the band, each met with worldwide success:
5 Seconds of Summer (2014),
Sounds Good Feels Good (2015),
Youngblood (2018),
Calm (2020),
5SOS5 (2022), and ''
Everyone's a Star!'' (2025). Apart from the band, Irwin has song-written and provided instrumentation for other artists, including
Andy Black,
The Faim and
Makeout. In 2024, Irwin announced the release of his second solo album, titled
Blood on the Drums, which was released on 17 July 2024. It was preceded by the single, "Straight to Your Heart", the track was described as an ’80s new wave-influenced alt-pop anthem, and was co-written and produced by Irwin in collaboration with John Feldmann. Unlike
Superbloom, which was created during the pandemic and focused on personal reflection,
Blood on the Drums takes a more outward perspective.
Blood on the Drums was released in two parts: The first eight tracks were released digitally on 12 June, with the complete album released on 19 July 2024. == Personal life ==