GSM means grams per square metre. It is the weight of the fabric, and it is the quickest way to describe how thick or light a garment will feel.
Quick reference
| Product | Typical GSM | Feel |
|---|---|---|
| Sublimated jersey | 130–160 | Light, breathable |
| Standard t-shirt | 160–200 | Everyday |
| Heavyweight tee | 220–280 | Structured, boxy |
| Leggings | 230–280 | Compressive, opaque |
| Hoodie | 320–450 | Warm, premium |
| BJJ gi jacket | 350–550 | Tough, grip-resistant |
Heavier is not always better
A 450 GSM hoodie feels premium in a cold climate but is too warm for an Australian summer. Match the weight to how and where the garment will be worn.
Fabric type matters too
Two fabrics with the same GSM can feel completely different. Fleece is brushed and soft inside; French terry has loops and breathes better. Ask for swatches before you decide.