Formerly, they were a duo, alongside rising musician Style of Eye, until he decided to part ways with the project shortly after their second album The Aviary in 2017.

[1] Karlsson has co-written and co-produced tracks for artists such as Katy Perry, Britney Spears, Jennifer Lopez, Kylie Minogue and Madonna.

Specifically, Karlsson co-wrote the Britney Spears single "Toxic", which eventually earned an Ivor Novello award (for songwriting and composition) and a Grammy for Best Dance Recording.

Linus Eklöw, known by his stage name Style of Eye, co-wrote and produced Icona Pop's song "I Love It" featuring Charli XCX.

In 2009, Karlsson's band Miike Snow asked Eklöw, who produces and DJs as Style of Eye, to remix their song "Animal".

"[3] There were many unfinished ideas that the pair fiddled with and then abandoned, but it wasn't until sometime in 2012 that things really came together, when they stopped the loop-based and software- approach common in modern dance music and switched to Karlsson's usual method of beginning a song on guitar or piano.

The duo figured out their own approach—once they create a foundation with a simple arrangement, they build it up with stirring keyboards, monumental drums, imploring vocals and inventive flourishes.

Recording in a studio in the Swedish archipelago in the Baltic Sea, the duo began to focus heavily on their artistic direction.

[16] Galantis released the single "Gold Dust" on 19 February 2015, through Stereogum and reached number 1 on Hype Machine's Popular Chart.

"Friend (Hard Times)" pairs a vocal with a deep house groove, while "The Heart That I'm Hearing" contains synths and a skittering rhythm.

On 30 September 2016, Galantis and Hook N Sling released the collaborative single "Love on Me" followed by a music video for the track on 4 October 2016, directed by Dano Cerny.

On 15 December 2016, they released a lyric video for "Pillow Fight", which the band has said "brings back the original Galantis heart and roots."

"[28] Subsequently, on 14 May 2018, the duo teased the release of their new single, "Spaceship" featuring Uffie, by posting a collage of all previous album covers, followed by a question mark.

The posts[29] and subsequent comments across social channels indicated that Galantis would premiere the song during their set at Hangout Music Festival, on 18 May 2018.

On 13 July 2018, the group released 2 songs called "Satisfied" featuring MAX and "Mama Look at Me Now" with a new album art cover of the seafox.

In January 2019, the band released a “sizzle reel” in which they confirmed a new single "Bones" featuring OneRepublic would be coming in 2019.

[31] Church consisted of fourteen songs and included collaborations with artists such as Yellow Claw, Passion Pit, Hook N Sling, Dotan, Dolly Parton, Mr. Probz and John Newman.

Galantis then collaborated with Pink Sweat$ and Ship Wrek on "Only a Fool", which was released on 29 May 2020, and with Jackson Wang of Got7 on the single "Pretty Please".

[citation needed] On 21 May 2021, Galantis released the single "Heartbreak Anthem" with French DJ David Guetta and British girl group Little Mix.

[41] The group's performances are characterized by them waving seafox flags, jumping from the stage, and doing other stunts that increase the energy of their shows.