Genryukan Aikido follows the current ranking or grade system as laid down by the British Aikido Association.
The details of the syllabus can be found on the BAA site here.
Below is a brief insight into the history and reasoning of the coloured belt system used by so many martial arts.
“The originator of the progressive grading system (or the Dan-i system) was Jigaro Kano, the founder of Judo. In the days before Kano created Judo, there was no kyu/dan ranking system in the martial arts.
A more traditional method of recognizing achievement was the presentation of certificates or scrolls, often with the secrets of the school inscribed. Kano started the modern rank system when he awarded shodan to two of his senior students (Shiro Saigo and Tsunejiro Tomita) in 1883. Even then, there was no external differentiation between yudansha (black belt ranks) and mudansha (those who hadn’t yet attained black belt ranking).
Kano apparently began the custom of having his yudansha wear black obi (belts) in 1886. These obi weren’t the belts worn today — Kano hadn’t invented the judogi (Judo uniform) yet, and his students were still practicing in kimono. They were the wide obi still worn with formal kimono. In 1907, Kano introduced the modern judogi and its modern obi, but he still only used white and black belt ranks. The white uniform represented the values of purity, avoidance of ego, and simplicity. It gave no outward indication of social class so that all students began as equals.
Professor Kano was an educator and used a hierarchy in setting learning objectives for Judo students, just as students typically pass from one grade to another in the public school system. The Judo rank system represents a progression of learning with a syllabus and a corresponding grade indicating an individual’s level of proficiency. Earning a black belt is like graduating from high school or college. It indicates you have achieved a basic level of proficiency, learned the fundamental skills and can perform them in a functional manner, and you are now ready to pursue Judo on a more serious and advanced level as a professional or a person seeking an advanced degree would. Of course, the rankings also represent progress towards the ultimate objective which is to improve the self not just physically, but morally as well.
Other coloured belts for students who had not yet achieved black belt originated later, when Judo began being practiced outside of Japan. Mikonosuke Kawaishi is generally regarded as the first to introduce various coloured belts in Europe in 1935 when he started to teach Judo in Paris. He felt that western students would show greater progress if they had a visible system of many coloured belts recognizing achievement and providing regular incentives.” – Courtesy of Neil Ohlenkamp, JudoInfo.com
So forget what you may have heard or read about belt history, and them originally becoming darker over time with blood and dirt, and because they are not washed. That is pure myth, frequently regurgitated to help perpetuate the ubiquitous mysticism that surrounds the “Black Belt”. Ranks can help some students (generally younger) who are inclined with goal setting and need their next target belt to help them feel they are making progress on their training journey. Quite simply the belts we wear are used as a rudimentary indicator of proficiency (not status) within the clubs in our association. They are also a visible means for coaches to immediately know how well a student can take ukemi for instance, and can help during lessons based on our training syllabus.
“In okinawa, belt mean no need rope hold up pants!” – Mr Miyagi, The Karate Kid
So forget what you may have heard or read about belt history, and them originally becoming darker over time with blood and dirt, and because they are not washed. That is pure myth, frequently regurgitated to help perpetuate the ubiquitous mysticism that surrounds the “Black Belt”.