About the Judo Gi Rules

Judo is a grappling sport with its origins in Japan. In competition, Judokas (i.e., judo practitioners) win matches by scoring points called ippon. Ippon are scored for throws, which occur when a Judoka knocks his opponent hard onto his back, for dominance, which occurs when a Judoka pins his opponent on his back and holds him there, and for submissions such as chokes or lock holds that force the opponent to submit.

Traditional competition Judo requires Judoka to wear a gi (i.e., the Japanese word for uniform). The gi is both a symbol of Judo's origin, as well as a practical garment for a sport that involves a great deal of tugging, twisting and maneuvering.

  1. History of the Judo Gi

    • The Judo gi evolved from the common kimonas worn by Japanese citizens centuries ago. The jacket flaps crossed the wearer's body and were held closed by a cloth sash tied around the waist. According the Judo Info Online Dojo, Dr. Jigoro Kano, a Japanese educator, created Judo by studying the combat techniques of Ju-Jitsu and transforming them into skills that could be used in a competition sport. He thus became Judo's first sensei, the Japanese word for Teacher. Sensei Kano's first students wore their everyday kimonas to practice, so he had them wear black sashes to keep the kimonas closed while they grappled. Eventually, Sensei Kano developed the Judo gi and its belt, which were specifically designed to withstand the wear and tear of the sport.

    Style of the Competition Judo Gi

    • The traditional competition Judo gi is comprised of a heavy jacket, lighter weight pants and a cloth belt. Gis are usually made from cotton or cotton blends and feel much like rugged canvas. Most are made with reinforced stitching to hold the garments together during grappling. Some include double layers of cloth in the knee and shoulder areas for endurance. As such, a high-quality competition gi feels very heavy on the body, and thus it is not comfortable to wear outside of the dojo (i.e., training hall). The belt is usually made from cotton. The color of the belt identifies the Judoka's rank. Lighter colors such as white and yellow indicate beginners, whereas darker colors such as brown and black represent advanced practitioners.

    Rules for Competition Judo Gi Sizes

    • Judokas who choose to enter formal competition as recognized by the International Judo Federation (IJF) must wear gis that are in alignment with the federation's rules. The size of a Judoka's gi is closely reviewed by judges, as one that is too loose or strangely cut may provide a Judoka with an unfair advantage. His arms or legs could go in one direction while his gi goes in another. According to the IJF, "The jacket shall be long enough to cover the thighs and shall at a minimum reach to the fists when the arms are fully extended downwards...The sleeves...must reach to the wrist joint at the maximum and 5 cm above the wrist joint at the minimum."

    Rules for Competition Judo Gi Colors

    • The traditional Judo gi is white. However, in competition, it is easier for judges to identify Judokas within matches if they are wearing different colors. Although martial arts suppliers sells gis in many different colorful designs, the IFJ's official rules state that competition gis must be all white or all blue. A Judoka must own both colors and be ready to change gis in mid-competition. The color a Judoka wears is designated by his placement on the competition slate, which could change with each passing round.

    Rules for Markings on Competition Judo Gis

    • Many Judokas wear patches and markings on their gis to designate their countries, the dojos at which they train or the sponsored teams to which they belong. The IFJ is specific in its rules regarding markings on Judo gis. These include the national Olympic abbreviation of one's country on the back of the jacket (11-cm letters), a national emblem (e.g., flag) on the left breast (100 cm) and some advertising for team sponsors on the sleeves (10 by 10 cm). The Judoka's name can be embroidered on his belt.

    Rules for Competition Gis for Female Judokas

    • The jacket of the Judo gi is only held closed at the waist by the belt, and during the grappling of the competition, it is often pulled out and flung wide open. For female Judokas, this presents an exposure problem. The IFJ specifically addresses this in its official rules, stating, "Female contestants shall wear under the jacket either a plain white or off-white T-shirt with short sleeves...long enough to be worn inside the trousers, or a plain white or off-white leotard with short sleeves.