Lewis was born in Redmond, Washington to Dallas and Dinah Lewis. Dinah is a former rocker who still sings and plays guitar. He is an only child and is of Welsh, German and Irish descent. He attended Kenmore Junior High and later Inglemoor High School in Kenmore, Washington. In high school, Lewis participated in many high school state competitions. He also took part in numerous musicals, as well as comedy and rap videos with his friends. In many of these videos, he portrayed his alter ego, Jimmie Walker Blue, the character he introduced during the semi-final round of American Idol.

Lewis started beatboxing at seventeen. He picked up this talent purely by ear, listening to CDs of beatboxing, after he was inspired by Matthew Selby, a former member of the Los Angeles-based a cappella group M-Pact, of which fellow American Idol semi-finalist Rudy Cárdenas was a member. Aside from singing and beatboxing, Lewis plays the guitar, keyboard, drums and has written many songs such as "Sh