Johann was born in Tallinn as the son of musician Tarmo Urb. At the age of ten Johann moved to live in Finland with his mother and at 17 he moved to the United States where he started his career in modeling and acting. He studied in the Lee Strasberg Theatre and Film Institute.
In 2001, Urb landed a small part in the film Zoolander. Later, he made an appearance in the short film Fear of Feathers and had a role in one episode of CSI: Miami. In 2004, Urb appeared in the short-running television series The Mountain. Following that, he guest starred in several television shows and made smaller film roles.
Urb got his first major film role in The Hottie and the Nottie in 2008. The following year, Urb made a short appearance in Roland Emmerich's disaster epic 2012 as a heroic pilot and he played a journalist in the fantasy TV-series Eastwick. He also played the part of Leon S. Kennedy in Resident Evil: Retribution, which was released in 2012.
