GSM stands for grams per square metre, and it is the single most useful number on a garment label. It tells you how much a square metre of that fabric weighs, which in practice tells you how the piece will hang, how opaque it is, and whether it will hold its shape after twenty washes.
Higher GSM means denser, heavier fabric. A 400gsm hoodie is roughly twice the fabric of a 200gsm one. That is the whole concept, and once you know it you can judge quality without touching the garment.
We build our range around specific weights rather than round numbers, and this guide explains why. If you want to see the pieces, browse our South African streetwear range.
Key Takeaways
- GSM means grams per square metre. It measures fabric density, not thickness, and it is the clearest quality signal a brand can publish.
- For t-shirts, 180gsm is standard high street, 240gsm to 270gsm is premium heavyweight. Ours sit in the second range.
- For hoodies, 280gsm to 320gsm is standard, 400gsm and above is heavyweight. Ours run 400gsm to 480gsm.
- 400gsm means a square metre of that fabric weighs 400 grams. On a hoodie that is a structured, warm piece that holds its shoulder line for years.
- Higher is not automatically better. A 400gsm t-shirt would be uncomfortable in a Durban summer. Weight has to match the garment and the climate.
- If a brand will not tell you the GSM, that is usually the answer.
What does GSM mean in clothing?
GSM means grams per square metre. Cut a one metre by one metre piece of the fabric, weigh it, and the number in grams is the GSM. A 260gsm cotton jersey means that square weighs 260 grams.
It measures density rather than thickness, which is an important distinction. Two fabrics can feel similarly thick while one is loosely knitted and light and the other is tightly knitted and heavy. The tighter, heavier one holds its shape. The looser one does not.
This is why GSM is a better quality signal than words like premium, luxury or heavyweight. Those are marketing terms with no fixed meaning. GSM is a measurement.
What does 400gsm mean in fabric?
400gsm means one square metre of that fabric weighs 400 grams. On a hoodie or sweatpant, that puts it firmly in heavyweight territory, well above the 280gsm to 320gsm most high street fleece sits at.
In practical terms, a 400gsm hoodie:
- Holds its shape when worn open or unzipped, instead of collapsing inward
- Keeps the shoulder line clean after repeated washing
- Is genuinely warm without a base layer in a Cape Town or Highveld winter
- Feels substantial in the hand rather than papery
Our Charcoal Black Zip Up Hoodie sits at 400gsm, which is the entry point for our hoodie range rather than the top of it.
What is a good GSM for a t-shirt?
For a premium heavyweight tee, look for 240gsm to 270gsm. Below roughly 200gsm the cotton goes translucent in pale colours and loses the structure an oversized cut depends on. Above about 300gsm a short-sleeve tee starts to feel like a sweatshirt.
A rough guide to what you will find on the market:
- 140gsm to 180gsm: standard high street tees. Light, cheap, and they lose shape quickly.
- 200gsm to 230gsm: mid-weight. Better, still soft, holds a relaxed shape reasonably well.
- 240gsm to 270gsm: premium heavyweight. Holds a boxy silhouette, opaque in any colour, survives years of washing.
- 300gsm and above: very heavy. Structured, but warm for a South African summer.
Most of our tees run at 260gsm, including the WAG Plain Off White T-Shirt. Our Vintage Grey T-Shirt goes heavier at 330gsm, which is deliberate for a piece designed around a lived-in, structured feel. You can see the full range in the t-shirt collection.
What is a good GSM for a hoodie?
Aim for 400gsm or heavier. Most high street hoodies sit between 280gsm and 320gsm, which is why they lose their shape within a season. The extra weight is what keeps the shoulder structured and the body from clinging.
Our hoodie range runs 400gsm to 480gsm:
- 400gsm: the Charcoal Black Zip Up. Warm without bulk, good for transitional weather.
- 460gsm: the Black Essential Hoodie. The core winter piece.
- 480gsm: the 22 Aged Black Hoodie. The heaviest in the range.
Sweatpants follow the same logic. Our Daily Unit Grey Sweatpants run at 400gsm so the leg hangs straight rather than clinging, and the rest of the relaxed trouser range sits between 400gsm and 460gsm.
Is 400gsm good for a hoodie in the South African climate?
Yes, for most of the country and most of the year. A 400gsm hoodie is the right base weight for Cape Town winters, Highveld evenings, and the twenty degree daily swings Johannesburg produces from May onwards.
Where it needs thought is coastal humidity. In Durban summer, a 480gsm hoodie is more than you need and a 400gsm one worn open over a heavyweight tee makes more sense than a heavier pullover.
The rule we work to: change the weight of the fabric as the season changes, not the cut or the colour. A 260gsm tee in January, a 400gsm hoodie over it in April, a 480gsm pullover in July. The silhouette stays the same, only the weight moves.
How to check GSM before you buy
Ask, and treat the answer as the test. A brand that builds around fabric weight will publish it on every product page. A brand that does not will describe the garment as heavyweight without ever giving you a number.
What to look for:
- A specific figure on the product page. 260gsm, not "premium heavyweight cotton".
- Consistency across the range. If the weights vary wildly with no explanation, the sourcing is inconsistent.
- Composition stated alongside it. 100% cotton at 260gsm behaves differently from a cotton-polyester blend at the same weight.
- Shape retention claims backed by weight. Anyone can say a piece holds its shape. The GSM tells you whether that is plausible.
If the GSM is not listed anywhere and support cannot tell you, assume it is at the light end. Brands that invest in heavier fabric advertise the fact, because it is the most expensive part of the garment.
Does higher GSM always mean better quality?
No. GSM tells you the weight of the fabric, not the quality of the cotton, the knit or the construction. A heavy garment made from poor fibre with sloppy seams is still a poor garment.
Weight also has to suit the piece. A 400gsm t-shirt would be unwearable through a South African summer, and a 200gsm hoodie is barely a hoodie. The right answer is the right weight for the garment and the climate, not the highest number available.
Read GSM alongside three other things: fibre composition, seam finish, and how the shoulder is cut. Together those four tell you almost everything. Alone, GSM tells you one useful thing very clearly.
Frequently asked questions
What does GSM mean in clothing?
GSM stands for grams per square metre. It is the weight of a one metre by one metre piece of the fabric, so it measures density rather than thickness. Higher GSM means denser fabric that holds its shape longer. It is the clearest quality signal a clothing brand can publish.
What does 400gsm mean in fabric?
400gsm means one square metre of that fabric weighs 400 grams. On a hoodie or sweatpant that is heavyweight, well above the 280gsm to 320gsm most high street fleece uses. It holds structure when worn open and keeps a clean shoulder line through repeated washing.
What is a good GSM for a t-shirt?
Look for 240gsm to 270gsm for a premium heavyweight tee. Below roughly 200gsm the cotton goes translucent in pale colours and loses the structure an oversized cut needs. Above 300gsm a short-sleeve tee starts to feel like a sweatshirt in South African heat.
What is a good GSM for a hoodie?
Aim for 400gsm or heavier. Standard high street hoodies sit between 280gsm and 320gsm, which is why they lose shape within a season. Our range runs from 400gsm in the Charcoal Black Zip Up to 480gsm in the 22 Aged Black Hoodie, weights that hold structure for years.
Is 400gsm good for a hoodie in South Africa?
Yes, for most of the country and most of the year. 400gsm is the right base weight for Cape Town winters and Highveld evenings. In coastal humidity it works better worn open over a heavyweight tee than as a heavy pullover. Change fabric weight by season, not cut.
Conclusion
GSM is grams per square metre, and it is the number that separates a garment built to last from one built to sell. 240gsm to 270gsm for tees, 400gsm and above for hoodies and sweatpants, and a brand willing to tell you either way.
We design and make our range in Cape Town, in limited runs with no restocks, and publish the weight on every piece. Browse the hoodie range or see the full collection. Minimal fashion, maximum confidence.
