The grading system we use at the University of Sheffield Judo club is defined by our governing body, the British Judo Association (you will hear people at the club refer to the BJA).
As you progress through the grades you are entitled to wear different colour belts, this gives people an indication as to your experience and knowledge within Judo.
The first grades, before the famous black belt, are referred to as kyu grades ('Q' grades).
Denoted by colour, the first grade you will earn will be the 6th kyu (red belt). The last grade before black is the 1st kyu, who wears a brown belt.
6th kyu : red belt
5th kyu : yellow belt
4th kyu : orange belt
3rd kyu : green belt
2nd kyu : blue belt
1st kyu : brown belt
The dan grades are the black belt wearers. The first 5 dan grades (all black belts) are achievable through Judo ability and knowledge.
From 6th dan and up, these grades are awarded for service to sport (coaching, reffing, representing the country etc) over a prolonged period of time.
10th dan is the highest grade, these are very rarely awarded. For example there are currently 2 UK 10th dans (July 2018).