Born in Queensland, where he attended Bribie Island State High School, King began refereeing at the age of 13.
[2][3] King became a fourth official in the A-League in 2014, and the following year he made his debut as a referee in the league by replacing the injured Alan Milliner in the last ten minutes of the match between Wellington Phoenix and Melbourne Victory.
[2] In September 2019, King was named as one of Football Australia's three full-time referees alongside Chris Beath and Shaun Evans, replacing Jarred Gillett who had moved to England; he had previously worked as a carpenter.
[6] King was appointed to the 2022 AFC Cup Final in Kuala Lumpur, Malaysia, as AVAR2,[7] and was awarded Referee of the Year for the 2021–22 A-League Men season.
He and City goalkeeper Tom Glover received head injuries by being struck with a metal bucket.