Badelt was born in Frankfurt, Germany. He started his musical career composing for many successful movies and commercials in his homeland. In 1998, Oscar-winning film composer Hans Zimmer invited Badelt to work at Media Ventures in Santa Monica, his studio co-owned by Jay Rifkin. Since then, Badelt has been working on a number of his own film and television projects such as The Time Machine and K-19: The Widowmaker. He also collaborated with other Media Ventures composers, such as Harry Gregson-Williams, John Powell, and Zimmer; and mentored several others like Ramin Djawadi and Steve Jablonsky.
While collaborating with Zimmer, Badelt contributed to the Oscar-nominated scores for The Thin Red Line and The Prince of Egypt, as well as writing music for many well known directors including Ridley Scott, Tony Scott, Terrence Mallick, John Woo, Kathryn Bigelow, Jeffrey Katzenberg, Werner Herzog, Sean Penn, Gore Verbinski, and Steven Spielberg.
Badelt co-produced the score to Hollywood box office hit Gladiator, directed by Ridley Scott, as well as writing portions of the score with singer/composer Lisa Gerrard. Having contributed music to Gladiator, Mission: Impossible 2 and Michael Kamen‘s score for X-Men, Badelt was involved in the three most successful movies in 2000. Badelt also collaborated with Zimmer on other successful films, such as The Pledge, and 2001 blockbusters Hannibal and Pearl Harbor. One of his more famous and popular scores was for the 2003 film Pirates of the Caribbean: The Curse of the Black Pearl.
Among Badelt’s most critically celebrated scores are the Chinese fantasy film The Promise and Dreamworks‘ remake of The Time Machine, the latter which earned him the Discovery of the Year Award at the World Soundtrack Awards 2003. He also wrote the music for the closing ceremonies at the Beijing Olympics in 2008, and was commissioned to write the opera about China’s First Emperor, to be premiered in 2011.
Additionally, Klaus worked on The Promise soundtrack for almost 6 months, which critics and fans consider as his best score. Also the song which can be heard in the movie’s end credits is an ancient folk song in China, and very few people can still sing it. As Badelt commented it, he traveled almost two weeks in China to find someone who is able to sing the whole folk song and could help him to rearrange it for the score.