The question of what is the best belt in karate is subjective and cannot be answered definitively. However, it is important to understand the ranking system of karate belts. In most karate styles, the highest belt is the black belt, which is divided into different degrees. The red belt is also considered the highest belt in karate, but it is reserved for exemplary masters of the art and is above the black belt.

It is worth noting that the belt ranking system varies between styles and schools, and there is no standard regarding karate belt colors. The belt colors and rankings depend on the style, school, and even country. The belt system in karate is used to symbolize the level of proficiency of the practitioner and their progress in the art.

In terms of the best brands for karate belts, Shureido is a well-known brand that is recommended for brown and black belts. However, the choice of brand is a matter of personal preference and does not affect the ranking or proficiency of the practitioner.