Seebach has written and produced songs for Danish and international artists since the late 1990s.

Together with his brother, Nicolai Seebach, he runs the production company Top Notch Music.

The two wrote the music for the charity song "Hvor små vi er" (English: "How small we are") for the victims of the 2004 Indian Ocean earthquake and tsunami.

His self-titled debut album consists of 12 tracks and was released on 28 September 2009, containing among others the singles "Engel" and "Glad igen" (English: "Happy again").

His brother Nicolai Seebach is also a well-known musician, songwriter and producer who co-writes most of Rasmus' materials.