[4] Daði was born in Reykjavík but grew up in Denmark until the age of nine, then his family moved to Iceland and settled in the Southern Region, first in Laugaland and later in Ásahreppur.

In 2014, he moved to Berlin, where he received a BA in music management and audio production at the Catalyst Institute for Creative Arts and Technology in 2017.

Later, singer Gunnlaugur Bjarnason and guitarist Guðmundur Einar Vilbergsson, whom he had met at the South Iceland Multicultural School, joined the band.

They were characterized by their signature teal green sweaters, which have pixel art portraits of themselves printed on them, as well as their faux "instruments" made of household items and discarded objects that Stefán, Jóhann, and Árný utilize.

[10] In June 2019, Daði released his debut album, & Co., an avant-garde pop record that has drawn comparisons to French electronic duo Daft Punk for its retro disco sound.

Daði & Gagnamagnið won six such competitions, in Austria (Der kleine Song Contest), Australia, Denmark, Finland, Norway, and Sweden.

[18] In 2023, he performed a cover of Atomic Kitten's "Whole Again" as an interval act during the final of the Eurovision Song Contest 2023, held in Liverpool, alongside a large number of look-alikes as well as his wife.