BJJ Gi Buying Guide: Weave, Sizing, and Care Explained

Image Credit: Photo by Hiruka komunikazio-taldea, via Flickr, licensed under CC BY-SA 4.0.

A BJJ gi is the heavyweight cotton uniform worn for gi jiu-jitsu training and competition, built to survive constant grip fighting without tearing at the collar or sleeve. Picking the right one comes down to three decisions: how the fabric is woven, what size actually fits your body under IBJJF rules, and how you care for it once you own it. Get any one of those wrong and you either overpay for durability you do not need, or you show up to a competition in a gi that gets you disqualified at weigh-in.

This guide walks through all three, plus the difference between training in a gi and training no-gi, since a lot of first-time buyers are not actually sure which one they need yet.

Understanding Gi Weaves

The weave describes how the fabric is constructed, while GSM refers to its weight, and it is the single biggest factor in how a gi feels, how long it lasts, and how much it costs.

1. Single Weave

Single weave gis use a lighter, more open weave, typically in the 350 to 450 GSM range. They are cooler to train in, dry faster after washing, and cost less up front. The tradeoff is durability: a single weave jacket wears through at the collar and cuffs faster under heavy grip fighting, so it suits students training two or three times a week more than someone on the mat daily.

2. Double Weave and Gold Weave

Double weave gis are thicker and heavier, often 550 GSM or more, with reinforced stitching at stress points. Gold weave sits in between, using a tighter weave pattern to get some of double weave's durability without the full weight. If you train five or more sessions a week, or you are hard on your gis specifically because you play a heavy grip-based game, the extra durability pays for itself over a year of use.

3. Ripstop

Ripstop gis use a woven-in grid pattern, usually on the pants and sometimes the jacket, that stops small tears from spreading into large ones. Ripstop is a lightweight, tear-resistant fabric commonly used for gi pants, but the pants in particular wear faster at the knees than a full-cotton weave.

Sizing a BJJ Gi

Gi sizing is not the same as clothing sizing, and it is the single most common reason a new gi gets returned. Manufacturers size gis by a combination of height and weight, and most publish a chart specific to that model, because cut varies even within the same brand.

• Measure your height and current weight, not your clothing size, and check them against the specific model's chart rather than a generic one.
• Expect a new, unwashed 100 percent cotton gi to shrink noticeably on its first hot wash, so many manufacturers size "pre-shrink" to account for this.
• If you are between two sizes, follow the specific brand's size chart and make sure the finished fit meets competition requirements, since IBJJF checks jacket and pant length at weigh-in.
• Sleeve length matters as much as body size: IBJJF rules require the sleeves to come no more than 2 cm from the wrist when your arms are extended straight out.
• IBJJF rules also require gi pants to reach no more than 2 cm above the ankle bone.

Shrinkage and Washing

A 100 percent cotton gi will shrink, and the goal is controlling when and how much rather than trying to prevent it entirely. Most gis are designed to shrink slightly on their first wash and then stabilize, which is why sizing charts are often written for the post-shrink fit rather than the fit straight out of the bag.

Wash in cold water on a normal cycle and hang dry whenever possible. Machine drying on heat is the single fastest way to shrink a gi further than intended, and repeated heat drying over months will eventually shrink a jacket out of a legal competition fit.

Gi vs No-Gi: Which Do You Need?

Gi jiu-jitsu is trained in the uniform described above, and the grips it provides change the entire grappling game, since collar, sleeve and lapel grips do not exist without fabric to grab. No-gi is trained in a rash guard and grappling shorts instead, and it rewards a faster, wrestling-influenced style since there is nothing to grip but limbs and body position.

Most schools teach both, and most competitive grapplers eventually train both, because the two rulesets reward different instincts and cross training each one sharpens the other. If your gym runs both gi and no-gi classes, budget for a rash guard and a pair of grappling shorts alongside your gi rather than treating it as an either-or purchase.

Competition Legality

If you plan to compete under IBJJF rules, buy IBJJF-legal from the start rather than discovering a problem at weigh-in. The rules cover fabric, gi thickness, permitted colors, sleeve and pant length, collar measurements, and patch placement. A gi bought purely for training does not need to meet every one of these, but a gi bought to compete in should.

Frequently Asked Questions

What GSM is best for a BJJ gi?

There is no single best GSM, since it depends on training frequency and climate. Most students training three or fewer times a week do well in a 350 to 450 GSM single weave, while daily trainers or heavy grip players benefit from a 550 GSM double weave's added durability.

How much does a BJJ gi shrink?

How much a gi shrinks varies by brand, fabric, and how it is washed and dried. This is why sizing charts are usually written to reflect the post-shrink fit rather than the fit straight out of the packaging.

Can I wash my gi in hot water?

You can, but a hot wash will shrink a new gi more than a cold wash will, and repeated hot washes will keep shrinking it over time. Cold water on a normal cycle is the safer default, with a single hot wash reserved for correcting a gi that has stretched out.

What is the difference between gi and no-gi training?

Gi training uses the heavyweight cotton uniform and its collar, sleeve and lapel grips, while no-gi is trained in a rash guard and shorts with no fabric to grip. The two rulesets reward different styles, and most competitive grapplers train both.

Do I need an IBJJF-legal gi to start training?

No. IBJJF-legal requirements only matter once you plan to compete under those rules. A gi bought purely for gym training does not need to meet every competition specification, though buying one that already does remove the risk of needing a second gi later.

How do I know what size gi to buy?

Check your height and current weight against the specific model's size chart rather than a generic chart or your clothing size, since cut varies by brand and even by model within a brand. If you are between two listed sizes and plan to compete, size toward your competition weight class.

Ready to find your size? Browse our full selection of BJJ gis and no-gi gear, in single weave, double weave and ripstop, or stop by Fighters Shop to try one on before you buy. If you train both gi and no-gi, check our gym bags and backpacks for something that fits a gi, a rash guard and shorts without leaving your gear soaking wet against your other belongings.