What GSM Means
GSM stands for grams per square metre — the weight of one square metre of fabric. It is the single best number for judging how thick or thin a cloth is, and it drives how a garment feels and wears.
Recommended GSM by Product
| Product | Recommended GSM | Why |
|---|---|---|
| T-Shirts | 180–220 g/m² | 220 g is the sweet spot — not thin, not heavy, wearable all year |
| Hoodies & Sweatshirts | 320–400 g/m² | Heavy enough to feel premium, hold shape, and take decoration |
| Sweatpants & Shorts | 280–350 g/m² | Balances structure with comfort for everyday wear |
How GSM Changes the Garment
- Hand-feel — higher GSM feels denser and more substantial in the hand.
- Drape — lighter cloth drapes and flows; heavier cloth stands away from the body.
- Warmth — more grams means more trapped air and more insulation.
- Cost — heavier cloth uses more yarn, so unit price rises with GSM.
Two More Numbers Worth Knowing
How We Help
Tell us the season and the look you want, and we will suggest a GSM and yarn match that hits your price point. When in doubt, 220 g for tees and 360 g for hoodies are our safe, proven defaults.
GSM Quick Reference
| Weight band | GSM | Feels like | Typical use |
|---|---|---|---|
| Light | 120–180 g | Airy, drapes, see-through risk | Summer tees, linings |
| Mid | 180–280 g | Balanced, all-season | Everyday tees, tops |
| Heavy | 280–400 g | Substantial, structured | Hoodies, sweatpants |
| Super-heavy | 400 g+ | Boxy, premium streetwear | Statement hoodies |
GSM vs Decoration
- DTG print — best on 180–220 g jersey; too light shows hand-feel, too heavy muffles detail.
- Embroidery — sits cleanest on 280 g+ terry/fleece; light jersey needs a backing.
- Silicone / puff print — needs 300 g+ to support the raised ink without cracking.
- Sublimation — polyester only, GSM matters less than fibre content.
GSM vs Hand-Feel and Cost: A Practical Table
GSM is the number buyers quote most often and understand least precisely. It is only one of several thickness-related measures, but it is the one that drives fabric cost, warmth and perceived quality most directly. The table below maps weight to what the wearer actually feels.
| Weight band | Typical use | How it feels | Cost effect |
|---|---|---|---|
| 150–180 gsm | Summer tees, lightweight tops | Thin, airy, drapes easily | Lowest fabric cost per metre |
| 180–220 gsm | Everyday cotton tees, promos | Balanced — the mainstream choice | Baseline for T-shirt pricing |
| 220–280 gsm | Heavyweight tees, premium basics | Substantial, holds shape well | Noticeably higher yarn content |
| 280–350 gsm | Sweatshirts, joggers, crewnecks | Warm, structured, holds a print well | Mid-to-high; the fleece mainstream |
| 350–450 gsm | Heavy hoodies, winter ranges | Dense and premium, takes 3D decoration | Highest — yarn-heavy and pricier per metre |
Three GSM Misconceptions
- Misconception: higher GSM always means better quality. Beyond the right band for a garment, extra weight makes it hot, stiff and expensive without adding value. A 400 g T-shirt is not a premium T-shirt — it is a heavy T-shirt.
- Misconception: GSM is a single fixed number per fabric. In practice every mill holds a tolerance, and 300 g fleece may arrive anywhere between roughly 285 and 315 g. Ask what tolerance the mill holds, and accept that a small variance between sample and bulk is normal.
- Misconception: GSM alone determines how a garment feels. Fibre content, yarn count, knit structure and finishing matter just as much. A 300 g brushed fleece and a 300 g french terry can feel entirely different to the hand.
How to Specify GSM in Your Tech Pack
A tech pack that says only "300gsm fleece" leaves several things open. To avoid a mismatch between what you ordered and what arrives, specify four values together.
- Nominal GSM — the target weight, for example 300 gsm.
- Acceptable tolerance — for example ±5%, so both sides know what passes.
- Fibre composition — for example 50% cotton / 50% polyester. Weight without composition does not define the fabric.
- Knit structure — brushed fleece, french terry, loopback or jersey. Two fabrics at the same GSM and the same blend can still behave differently.
FAQ
Is higher GSM always better?
No. A 400 g tee is hot and stiff; a 180 g hoodie feels flimsy. Match GSM to the garment, not to a bigger number.
Does GSM affect price much?
Yes, linearly — each extra 20 g means more yarn per metre. Moving a hoodie from 320 g to 400 g adds a visible but modest cost.
Can I request a custom GSM?
Within reason, yes. We knit custom weights for OEM runs; for POD we keep a standard set (180 / 220 / 320 / 360 g) ready to go.