Step into any premium streetwear conversation and you will hear the number before you see the garment. 500GSM. Heavyweight. The kind of fleece that stands up on its own, holds a shape, and tells everyone in the room you did not buy it from a marketplace bundle.
But what does that number actually mean, and is 500GSM genuinely better than 400GSM? Here is the plain-English version - what GSM measures, how a 400GSM hoodie and a 500GSM hoodie differ in the hand, and how to choose the weight that fits how you actually wear your kit.
What GSM Actually Measures
GSM stands for grams per square metre. It is a measure of fabric density: the mass of one square metre of the cloth. Higher GSM usually means a thicker, denser, more substantial fabric, because more yarn has been knitted into the same area.
It is worth being precise here, because GSM is not a perfect quality score on its own. Two fabrics at the same weight can behave very differently depending on the yarn, the knit and the finishing. What GSM does give you is a reliable guide to how heavy and dense the fleece will feel, and how much structure it will bring.
For cotton fleece hoodies and tracksuits, the ranges most shoppers meet look roughly like this:
- 280-320GSM: lightweight to mid-weight, the standard high-street hoodie
- 350-400GSM: mid-heavyweight, noticeably denser with a better drape
- 450-500GSM+: heavyweight, the premium tier with real body and warmth
400GSM vs 500GSM: The Differences You Actually Feel
Warmth and insulation
A 500GSM fleece traps more air within a denser knit, so it holds warmth more effectively than a 400GSM piece. On a cold morning in Manchester or a late-night walk home, that difference is obvious. A 400GSM hoodie is a solid everyday layer; a 500GSM hoodie is the one you reach for when the temperature drops and you still want to look sharp rather than bundled.
Structure, shape and drape
This is where heavyweight fleece separates itself. A 500GSM hoodie holds its shape across the shoulders and chest instead of collapsing into folds. The hood stands with presence rather than drooping. The body of the garment keeps a cleaner line, which is exactly what gives premium streetwear its silhouette. A 400GSM piece will feel softer and more relaxed, but it will not carry that same sculpted shape.
Durability and how it ages
Denser fabric generally resists thinning at the elbows, cuffs and hem better than lighter fleece. A 500GSM piece tends to keep its weight and structure through repeated washing, where lighter fleece can lose body over a season. That is a large part of why heavyweight garments hold their look for longer.
Weight and how it wears
Nothing is free. A 500GSM hoodie is heavier to wear. Some people love that grounded, substantial feel; others find it too much for year-round wear. A 400GSM hoodie sits in the sweet spot for layering under jackets or for warmer days, where a 500GSM piece can feel like overkill.
Price
Heavier fabric simply uses more raw material and more knitting time, so 500GSM garments cost more to produce - and that is reflected in the price. A 400GSM hoodie usually lands at a lower price point; a 500GSM piece sits firmly in the premium tier.
Why 500GSM Costs More
There are two honest reasons. First, material: a denser knit uses more cotton yarn per garment. Second, process: heavyweight fleece is harder to knit, cut and finish, and it takes longer to produce consistently well. Brands that commit to 500GSM are choosing to spend more on the cloth itself instead of on shortcuts, which is why the weight has become shorthand for a premium build.
How to Choose Between 400GSM and 500GSM
Choose a 400GSM piece if you want:
- an everyday hoodie you can layer year-round
- a lighter, softer feel against the skin
- a lower price point without dropping into flimsy high-street fleece
Choose 500GSM if you want:
- maximum warmth and a substantial, grounded feel
- a hoodie or tracksuit that holds its shape and silhouette
- a garment built to age well and stay looking premium
For most people building a serious wardrobe, the answer is both. A mid-weight set for everyday rotation and a heavyweight piece for the days you want the fit to do the talking.
Where Heavyweight Fits at VELLURE
Heavyweight construction is central to what VELLURE UK is about. The Grey Acid-Wash 500GSM Signature Hoodie is a limited-edition build: full 500GSM cotton fleece in a distinctive acid-wash finish, made to carry the silhouette that heavyweight fabric makes possible. It is the clearest example of the brand's approach - you can see the structure in the shape alone.
If you want heavyweight warmth in a full co-ord, the tracksuit range brings the same premium density into a complete set. Browse the VELLURE Hoodies and VELLURE Tracksuits to compare weights, colours and fits side by side, then match your pieces across a look rather than buying them one at a time.
Looking After Heavyweight Fleece
Heavyweight fleece rewards a little care. Wash it inside out on a cool cycle, avoid high heat in the dryer, and let it air-dry where you can. Skip the fabric softener, which coats the fibres and dulls the hand of the cloth. Treated well, a 500GSM piece keeps its density and shape far longer than lighter fleece, which is where the investment pays back.
The Short Version
GSM measures fabric density, and density drives everything you feel: warmth, structure, durability and price. 400GSM is the soft, layerable everyday middle ground. 500GSM is the premium tier - warmer, more sculpted, built to hold its shape and last. Neither is automatically better; they are two tools for two jobs. Know what each one gives you, and you will buy the right weight every time.
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