[2] He initially came to widespread public attention at age 17 through a YouTube video, "Pop Culture", where he performed a mash-up of 39 different popular songs in real-time using a Novation Launchpad.

A clip of Leclercq performing his mash-up "Pop Culture", uploaded to YouTube on 11 July 2011, propelled him to international fame.

[3] According to a Reddit AMA he hosted in November 2019, he had the idea, purchased the Launchpad, and recorded the song all on the same day.

[citation needed] His live recorded performance debut was for Pete Tong's BBC Radio 1 gala event in Hull on 27 January 2012, where he played a 20-minute-long set.

[12] He later worked with Gaga on three tracks, "Gypsy", "Mary Jane Holland", and "Venus" on her third studio album, Artpop.

"[18] On 25 February 2014, Leclercq released a track available for a free download on his website called "Cut the Kid", stating that it was created c. 2011 or 2012.

Many of his songs have been used in media franchises: "Icarus" was featured in the US show Dancing with the Stars in May 2012 and 21 May 2013 (finals with Aly Raisman), on the in-game soundtrack of Forza Horizon, and the animated film The Mitchells vs. the Machines; "Finale" and "Imperium" have been featured in EA Sports' FIFA 13 and FIFA 15 respectively.

[citation needed] "Finale" and Leclercq's remix of "The Night Out" by Martin Solveig were featured on the official soundtrack of ESPN's Winter X Games XVII event in Tignes, France and both received several plays on air.

[23] In mid-2015, Leclercq embarked on his first headlining tour, Adventure Live, consisting of 22 stops in North America.

Leclercq further promoted his debut studio album on his Pixel Empire US Tour in early 2016, which ended on 21 February 2016.

On 29 May 2019, the goodfaith.world website was updated with a video[31] previewing the new song, titled "All My Friends", along with locations of record stores in four cities: Los Angeles, New York, Ålesund, and Nantes.

[36] The Good Faith Live tour was premiered at Lollapalooza 2019,[37] followed by headlining shows in London, Amsterdam, and Paris.

A longer North American leg started on 30 October in Vancouver and ended on 14 December in Austin, followed by an Australian tour as part of FOMO Festival in January 2020.

On 18 September 2021, Madeon premiered the Good Faith Forever Live set at Second Sky music festival in Oakland, California.

[45] After many years of being played during live performances and teased online, Madeon released the track "Love You Back" on 27 April 2022, after a reveal at his Coachella 2022 set.