At age 10 he started his education in acting at the theaterschool for youth in Amsterdam (AJTS).
Two years later, Koomen played a role in the movie Simon, directed by (Eddy Terstall, 2004).
The movie won in 4 categories of the National Dutch Film Awards (Gouden Kalveren).
Koomen also played in the independent movies Diep, (Simone van Dusseldorp, 2005) and “Tussenstand” by Mijke de Jong.
Amongst them: Valdrift (Jasper Wessels, 2010) and Mijn Marco (Sarah Verweij, 2011).He also guest starred in a variety of television series such as Van God Los (2012) and GTST (2014).