Swedish singer, songwriter and music producer, born May 28, 1973 in Stockholm.

He owns the music studio Limestone, founded in 1999. In the same year, he got a contract with Universal Music Publishing Scandinavia, where he is now listed as a songwriter. Over the years he has written songs for artists and groups such as Katharine McPhee, Paul Stanley of Kiss, BoA, Robyn and the Three Graces.

Popular songs Sommerdahl has written include My Destiny, which was sung by Katharine McPhee and performed on American Idol - Season 5 in 2006. The song was released as a single in June 2006 and reached number two on the US Singles Chart.

In 2008, he collaborated with American producer Desmond Child as producer for the fifth album by the Finnish rock group The Rasmus, Black Roses. The album was released in September 2008 and immediately topped the Finnish album chart.