Gunnar Karel was born in Reykjavik, Iceland in 1984. He started studying music at an early age and has played a diverse range of instruments. He studied compostion at the Icelandic Academy of the Arts with Tryggvi M. Baldvinsson and Úlfar Ingi Haraldsson. Completing a B.A. in 2010. Thereafter he studied in Copenhagen where he completed a M.Mus. in 2012 and a Solist diploma (Advanced post-graduate diploma) in 2014. His teachers in Copenhagen were Bent Sørensen, Hans Abrahamsen, Jeppe Just Christensen, Juliana Hodkinson og Niels Rosing-Schow. As a composer Gunnar mainly focuses on chamber music as he finds that his music gets the attention it deserves in smaller setups. Besides his composing he has been making his mark as concert producer. He founded the Sonic festival in Copenhagen with Filip C. de Melo in 2012. He is also one of the curators for the Peripheriberry concert series in Reykjavik.

Gunnar is a member of the Danish Composer Society, the theater group 16 elskendur and S.L.Á.T.U.R.