It varies greatly between styles and dedication. I have been in American Kenpo for a little over two years, and I am at red belt. I will be until August, when I take my brown belt test.    White: 1 month   Yellow: 3 months   Orange: 4 months   Purple: 4 months   Blue: 5 months   Green: 7 months   Red: 4 months so far    I learned fairly quickly and made more testing sessions than most other people, so I could probably pickup black in another year, maybe year and a half. thats 3-4 years total. Problem is the location that I am moving to late in August has no kenpo studios nearby, so I am switching styles.   Maybe if I move back to my hometown here and marry my HS Sweetheart after college, I will complete my black belt in AK.