As with other martial arts, a student’s progress is marked with a series of colored belts. In Brazilian Jiu Jitsu, the rank of Black Belt can only be conferred to adult individuals who have achieved a high degree of technical mastery and/or competitive success.
The belts in order are: White, Blue, Purple, Brown and Black. Some schools also award stripes to mark a student’s progress from White through Brown belts. Black Belts are typically awarded one stripe every three years up to ten stripes. There are special classifications for Black Belts fighter and instructors. Instructors have Black Belts with Red bands and Black Belts who are not instructors often (but not always) have White Bands. Typically, Black Belt instructors are not allowed to promote others up to Black Belt rank until they receive their second degree.
The ranks for children are different. Blue through black belts have minimum age requirements, so children have the following ranks beginning with Gray, Yellow, Orange and Green. Each belt has 4 stripes. These belts are utilized until the age of 16.
You can find a chart of the International Brazilian Jiu Jitsu Federation’s belt ranking system at: http://ibjjf.org/wp-content/uploads/2014/02/IBJJF-Graduation-System-Poster.pdf