BJJ Gi Fabric Guide: Weaves, GSM & Construction
The short answer
A BJJ gi is really two fabrics and a set of reinforcements. The jacket is a dense weave built to survive constant gripping; the trousers are a lighter woven cloth built for mobility; and the stress points carry extra layers of stitching. The standard build is set out below.
| Component | Standard specification |
|---|---|
| Jacket | Pearl weave or single weave, cotton or poly-cotton, 350-550 GSM |
| Trousers | 8-12 oz cotton ripstop or twill |
| Collar | Cotton-wrapped foam or rubber core; stiff to resist grips, quick to dry |
| Reinforcements | Multiple-stitched seams at armpits, side vents, knees and crotch |
| Drawstring | Rope or flat cord through multiple belt loops |
| Closures and trim | Contrast stitching, embroidery and woven patches to the club's design |
The choices that actually change how a gi feels and lasts are the jacket weave, the jacket weight, and the trouser cloth. Each is covered below.
Gi weaves compared
Gi jacket fabrics are named by their weave, the pattern in which the yarns interlace, and the weave decides the strength-to-weight ratio of the jacket. Pearl weave has replaced most of the traditional weaves because it delivers the most tear resistance per gram.
| Weave | Typical jacket weight | Character | Chosen for |
|---|---|---|---|
| Single weave | 350-450 GSM | Light, simple, less abrasion-resistant | Entry-level gis, hot climates, lightest weigh-ins |
| Pearl weave | 350-550 GSM | Tight weave with a pearl-like knotted surface; strong for its weight, dries fast | The standard modern gi, from light competition cuts to heavy training jackets |
| Gold weave | Around 550 GSM and up | Traditional midweight weave, softer with wear | Traditionalists; largely superseded by pearl weave |
| Double weave | 650 GSM and up | Very heavy and stiff, hard to grip | Judo more than BJJ; heavier than most BJJ rulesets and training rooms need |
ZipaSports manufactures gi jackets in pearl weave and single weave at 350-550 GSM in Sialkot, Pakistan, which covers the range from lightweight competition gis to heavy daily-training jackets; gold and double weave are listed above because buyers will meet the terms when comparing gis.
GSM and ounces: how gi weight is measured
Gi jackets are specified in GSM, grams per square metre of fabric, while trousers are usually quoted in ounces per square yard. The conversion is fixed: 1 oz/yd² is about 33.9 GSM, so an 8 oz trouser cloth is roughly 270 GSM and a 12 oz cloth roughly 405 GSM.
Two cautions when comparing gis. First, fabric weight is not garment weight: a "450 GSM gi" describes the jacket cloth, not what the whole gi weighs on a scale, and total weight also depends on cut, size and trouser choice. Second, heavier is not automatically better. A 550 GSM jacket resists abrasion and grips longer, but it is hotter to train in, slower to dry and heavier at a competition weigh-in, where competitors weigh in wearing the gi under most rulesets. Many competitors keep a light 350-450 GSM gi for competition and a heavier one for daily training; how many gis that adds up to depends on training frequency and drying time between sessions.
Ripstop vs twill trousers
Gi trousers are not cut from the jacket weave; they use a flatter woven cloth that trades some abrasion resistance for mobility and faster drying. The two standard options are ripstop and twill, both in the 8-12 oz range.
| Trouser cloth | Typical weight | Structure | Character |
|---|---|---|---|
| Ripstop | 8-10 oz | Plain weave with a visible grid of heavier reinforcing yarns | Light, fast-drying; the grid stops small tears spreading |
| Twill | 10-12 oz | Diagonal weave, the same family as denim and chino cloth | Softer drape, heavier, traditionally the more comfortable option |
Both are reinforced at the knees and crotch, where trousers fail first, and closed with a rope or flat drawstring through multiple loops so the waist stays put through stand-up exchanges. Competition rulesets in some federations restrict ripstop for jackets but generally allow it for trousers; buyers supplying competitors should check the current rules of the target federation before finalising specs.
Cotton vs poly-cotton, and shrinkage
Gi fabric is either 100% cotton or a poly-cotton blend, and the practical difference is shrinkage and drying time. Cotton shrinks when washed hot and tumble-dried, which is why gi size guides distinguish pre-shrunk (sanforised) fabric from unshrunk fabric that is deliberately cut long to shrink to size. Poly-cotton blends shrink less, dry faster and hold colour well, at the cost of the traditional all-cotton feel.
For custom orders the choice usually follows the market: competition-focused club gis stay with cotton pearl weave for the traditional feel and federation acceptance, while academies ordering student gis in volume often prefer poly-cotton for its stability across hundreds of wash cycles. Either way, the fabric should be specified together with the size chart, because a gi cut without accounting for the fabric's shrinkage behaviour will fit differently after ten washes than it did out of the bag.
Competition rules and colours
Most BJJ federations, the IBJJF among them, require gis in plain white, royal blue or black, made of cotton or cotton-like fabric, with jacket and trousers of matching colour and with sleeve and trouser lengths checked at gi inspection. Patch placement is also regulated, with specific zones where club and sponsor patches are permitted.
For a club or brand ordering custom gis, the safe pattern is: pick one of the three standard colours for the base, keep the weave to cotton pearl or single weave for competition models, and put the identity into embroidery, patch placements and contrast stitching rather than non-standard base colours. Rulesets are updated, so check the current gi requirements of the relevant federation before a competition-specific production run; training-only gis are not bound by any of this.
Ordering custom gis
ZipaSports manufactures custom BJJ gis, judo uniforms and karate uniforms in Sialkot, Pakistan: pearl weave and single weave jackets at 350-550 GSM, 8-12 oz ripstop or twill trousers, with multi-head embroidery, woven patches, custom contrast stitching, woven neck labels and full private-label packaging. Sizes follow fully custom charts for men's, women's and youth cuts.
Minimum order is 20-25 pieces per design, lower quantities are possible on request, and there is no MOQ limit for sportswear brands and companies. A free digital design mockup arrives within 24 hours; a physical sample takes 5-7 days, is charged at sample cost, and that cost is credited against your bulk order. Bulk production runs 15-25 business days after design approval. Pair the gi order with sublimated rash guards for a complete club package.
Frequently Asked Questions
What is pearl weave in a BJJ gi?
Pearl weave is a tight cotton or poly-cotton weave whose surface shows small rounded knots like rows of pearls. It is the standard modern gi jacket fabric because it gives the most tear resistance for its weight and dries quickly, typically at 350-550 GSM.
What GSM gi should a beginner buy?
A 450-550 GSM pearl weave jacket is the usual recommendation for daily training: heavy enough to survive constant gripping, without the stiffness of traditional double weave. Competitors often add a lighter 350-450 GSM gi for weigh-ins.
What is the lightest BJJ gi fabric?
Light single weave and lightweight pearl weave jackets at around 350 GSM, paired with 8 oz ripstop trousers. That combination is chosen for hot climates and for competitors cutting close to a weight limit, since most rulesets weigh athletes wearing the gi.
Do cotton gis shrink?
Yes. 100% cotton gi fabric shrinks with hot washing and tumble drying, so size guides distinguish pre-shrunk (sanforised) gis from unshrunk ones cut long to shrink to size. Poly-cotton blends shrink noticeably less. Cold washing and air drying minimise shrinkage either way.
What are gi trousers made of?
Gi trousers are 8-12 oz cotton ripstop or twill, not the jacket weave. Ripstop (8-10 oz) is lighter and tear-resistant thanks to its reinforcing grid; twill (10-12 oz) is softer and heavier. Both are reinforced at the knees and crotch.
What is the minimum order for custom BJJ gis?
20-25 pieces per design. Lower quantities are possible on request, and there is no MOQ limit for sportswear brands and companies. ZipaSports provides a free digital mockup within 24 hours and produces bulk orders in 15-25 business days after design approval.