Rank in Judo first five are colored black, 6th, 7th, and 8th "dan" have alternating red and white panels (dandara), and for 9th, 10th "dan" and above, the belts are solid red. In judo's promotion system as originally finalized by Kanō around 1926 there was no maximal dan rank, and judoka holding 10th dan would normally wear a red belt, but also could wear a white belt, the same color as the lowest kyū rank. However, since the highest dan rank reached in judo for a living person or conferred posthumously remains 10th dan, any judo dan rank higher than 10th dan is
Judo were called ; and only those of 4th "dan" or higher were called "judoka". (The suffix , when added to a noun, means a person with expertise or special knowledge on that subject). A judo teacher is called . The word "sensei" comes from "sen" or "saki" (before) and "sei" (life) – i.e. one who has preceded you. In Western dojo, it is common to call an instructor of any "dan" grade "sensei". Traditionally, that title was reserved for instructors of 4th "dan" and above. Judo practitioners traditionally wear white uniforms called or . sometimes abbreviated in the west as