Master is a very misunderstood term that is often misused. Traditionally in Okinawan and Japan a master was no less than 4th degree black belt. HOWEVER titles and belt ranks do not go hand in hand. In other words you do not become a master by reaching any belt rank. The title is given by the organization, ONLY to those that it feels are worthy of it. Everyone does not get a title, master, ...etc by simply earning a rank. As such each organization has different minimums for issuing a master title. some will give it to a person of 4th degree black belt. some don't consider 4th degree a master,. some styles require 5th degree minimum. some do not consider it until the person is sixth degree black belt. Again it is up to the organization to decide. A person can be as high as 7th degree black belt and still not be a master. They can be legitimate yet not a master. IF, a masters title is awarded, it is properly done in writing. There are two ways...... some organization write the title on the persons rank certificate... Other issue the title on a separate certificate that is only for the title. So as you see there in no set way it is properly done. The only sure thing is that if the title is not given , it is not assumed because of a rank earned. The other thing is that it is never given to anyone under 4th degree black belt, Ever !!!
By the Way..... The Korean styles copied the rank system used by the Okinawan's and Japanese. However they have neglected to follow the strict guidelines used by them. In Korean schools they for some reason believe that if a person reaches a set rank (usually 4th degree black belt), you are automatically a master, how convenient. That is why there are so many guys claiming to be masters that by Okinawan or Japanese traditions may or may not be a master. No art should assume that everyone of a certain rank is automatically a master. That would make most of them a joke.
EDIT: masters may wear one of several types of belts. In Okinawa and Japan some wear a black belt. At other times they may wear a Renshi belt (is black on the back side, the front is a red strip and a white stripe running beside each other from one end of the belt to the other. Usually if a 4th degree black belt wears it the white strip in place so it os on top of the red stripe. At 5th degree the belt is flipped over so that the red strip is on top.) The Hanshi belt is a belt made of panels sewn end to end. The panels alternate red, white, red, white,...... The Hanshi belt is usually used for 6th degree black belt and higher.
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