9th Wonder's first significant career breakthrough came in 2003 when, as an up-and-coming producer, he released an unofficial remix album of Nas' 2002 album God's Son entitled God's Stepson. Released through internet outlets, the album garnered significant attention and acclaim. The producer has said that he was not thinking in terms of using it to generate a buzz or promote his skills and that at that point: "I never thought any of this of me as a producer was going to happen." The album has since been credited as starting the now regular trend for unofficial 'home-made' remixes of whole albums.
9th Wonder began his career as the main producer for the group Little Brother. As part of Little Brother he gained recognition and critical acclaim for his production on their debut 2003 release, The Listening. Jay-Z's studio engineer Young Guru was impressed with his work, and contacted 9th Wonder, which led to 9th Wonder producing "Threat" for Jay-Z's 2003 The Black Album. The cut proved to be a mainstream breakthrough for 9th Wonder, most immediately in the major production role he secured on Destiny's Child's 2004 Destiny Fulfilled album that Jay-Z was instrumental in helping bring about. On the album, 9th Wonder produced the tracks "Girl" and "Is She the Reason," plus the bonus track "Game Over".
9th Wonder left Little Brother in 2007.
On October 29, 2007, 9th Wonder made a rare public appearance on BET's Rap City, alongside collaborator Talib Kweli. Madlib, Jean Grae and Erykah Badu appeared as well. In 2010, he appeared on BET's 106 & Park countdown with David Banner.
9th Wonder, E. Jones, and rapper J. Cole served as the lead producers of the soundtrack to the EA Sports video game NBA Elite 11. 9th Wonder and J. Cole also appear as "secret characters" in NBA Jam with a team name of Cole & Wonder.
9th Wonder debuted his rapping alter-ego 9thmatic in late 2009. 9thmatic appeared on songs with Khrysis and Sean Boog, Big Remo, Murs and Thee Tom Hardy.
9th Wonder worked with Mississippi rapper David Banner on a collaborative album entitled Death of a Pop Star which was released on December 21, 2010.