IBJJF legal describes a BJJ gi that meets the rules set by the International Brazilian Jiu Jitsu Federation for use in its sanctioned competitions. The rules cover areas such as jacket and sleeve length relative to the arm, pant length, fabric material and stiffness, and overall gi weight.
Officials at IBJJF events typically check a gi before matches, using a set of measurement gauges to confirm that sleeves, cuffs and the jacket skirt fall within allowed ranges, and that the fabric is not stiffened in a way that would make it harder for an opponent to grip. A gi that fails this check can be required to be swapped before competing.
For training and non IBJJF competitions, these exact measurements are far less important, and most practitioners choose a gi mainly for weave, weight and fit rather than tournament specification. Anyone planning to compete under IBJJF rules should measure their gi against the current published limits well before the event. See our gi sizing and shrinkage guide for related sizing advice.
