When a T-shirt is described as 220 GSM and a hoodie as 500 GSM, the number is telling you something useful—but not everything. GSM means grams per square metre. It measures the weight of a fabric over a fixed area.
In streetwear, GSM is one of the fastest ways to understand whether a garment is likely to feel light, substantial, structured, or extremely heavy. It does not automatically tell you whether the fabric is better. Fiber content, knit, finishing, construction and fit still matter.
What does GSM mean in clothing?
A higher GSM generally means more fabric mass per square metre. If two fabrics use similar fibers and construction, the higher-GSM fabric usually feels denser and more substantial.
- Around 180–220 GSM: lighter to midweight tops and layering pieces.
- Around 250–350 GSM: substantial tees, waffle pieces, sweatshirts and lighter fleece.
- Around 400 GSM: clearly heavyweight fabric with more structure.
- 500 GSM and above: very substantial hoodies, sweats and statement-weight garments.
Is higher GSM always better?
No. The right weight depends on the garment. A long sleeve meant to layer can work beautifully at 220 GSM, while a boxy tee designed to hold its shape may benefit from 350–400 GSM. A 500 GSM hoodie makes sense when the goal is density, warmth and a pronounced silhouette.
That is why RUE BÉNI uses different weights across the collection instead of forcing every piece into the same number. The 220 GSM Waffle Raw-Edge Long Sleeve is designed as a textured layer, while the 400 GSM RB Paris Boxy Tee is intentionally more architectural.
What does 400 GSM feel like in a T-shirt?
A 400 GSM tee is significantly heavier than a typical everyday T-shirt. The extra mass helps the fabric fall away from the body instead of clinging to it, which can make a boxy silhouette look cleaner. It also tends to make collars, sleeves and hems feel more substantial.
Explore the RUE BÉNI T-shirt collection to compare 300, 350 and 400 GSM options.
What does 500 GSM feel like in a hoodie?
At 500 GSM, a hoodie enters true heavyweight territory. It should feel dense in the hand and visually substantial when worn. The fabric weight can help the hood and body hold shape instead of collapsing, although the exact effect still depends on fleece, fiber blend and construction.
The RB Paris 500 GSM Heavyweight Hoodie uses that weight as part of the silhouette rather than as a specification for its own sake.
What about 530 GSM sweatpants?
Heavy bottoms behave differently from tops. A 530 GSM sweatpant can create a dense, structured leg with a more premium hand-feel, but fit and waistband construction become especially important. The RUE BÉNI 530 GSM Heavyweight Sweatpants use the extra weight with a regular fit and cuffed ankle rather than an exaggerated oversized shape.
How should you choose GSM?
Start with the result you want, not the biggest number. Choose lighter weights when you want layering and mobility. Choose 300–350 GSM when you want substance without extreme heft. Choose 400 GSM and above when structure, drape and a visibly heavyweight silhouette are part of the design.
GSM FAQ
Is 300 GSM heavy for a T-shirt?
Yes. For a short-sleeve tee, 300 GSM is already substantial compared with many standard everyday T-shirts.
Is 400 GSM too heavy for a T-shirt?
Not if the garment is designed around the weight. A boxy or oversized cut can use 400 GSM very effectively because the fabric helps define the silhouette.
Is 500 GSM good for a hoodie?
It is an excellent weight when you specifically want a dense, heavyweight hoodie. It may be more than necessary for warm climates or lightweight layering.
Does GSM tell you quality?
GSM tells you weight, not quality. Construction, fiber composition, stitching, finishing, fit and durability have to be judged separately.
Explore: RUE BÉNI Drop 001 for pieces ranging from 300 GSM to 530 GSM.
Start with the complete guide: Heavyweight Streetwear Guide: Fabric, Fit & Care.