The gi is the most important piece of equipment in martial arts and is considered the most essential to mastering the art of Brazilian Jiu Jitsu. Its color doesn’t have any specific connotation in BJJ, but different instructors may place some significance on it.

In traditional Japanese judo, the founder Jigoro Kano set white as the standard for the gi due to its association with purity and truth. For many other martial arts with Japanese roots, white is still the preferred gi color as it is believed to symbolize the purity of new students and their commitment to the discipline. In a few styles, the color of a gi or uniform can connote rank, membership in certain programs and other meanings. These are usually set by the system’s founder for reasons of uniformity in class or to convey a tradition that they felt the style needed to retain.

During competitions, fighters are required to wear basic colors such as white, blue or black gis. This makes it easy for referees and judges to see fighters easily and distinguish between them. Despite this, you will often see fighters wearing a rainbow or camo colored gi for the sake of fashion and because their instructor allows them to do so.

In the case of BJJ, most BJJ schools have no restrictions on Gi colors except for white and blue gis. White gis are regarded as the classic gi for most BJJ systems and a majority of students will train in a white gi. In some cases, however, a student’s instructor may allow them to train in a different color gi such as blue or black depending on the style of jiu jitsu they practice and their individual preference.

The only time when the gi color really matters is in the case of competitions that are held under the rules of the International Brazilian Jiu Jitsu Federation (IBJJF). In these competitions, fighters can only compete in Gis that are either white, blue or black.

While the blue gi was developed for pragmatic purposes and doesn’t carry any specific significance in most styles that use it, it has become very popular in hybrid martial arts systems where it is used in regular training as well as competitions.

When choosing a gi, it is best to run it by your instructor before purchasing it. This will ensure that you don’t buy a Gi that your instructor will not allow you to train in and it will also make sure that you are picking a gi that fits properly and is of good quality.