What Is GSM in Fabric?
What GSM means, how heavy your fabric should be, and how to choose the right one.
What is GSM?
GSM means grams per square metre— the weight of a fabric. The higher the number, the heavier, thicker, and usually more premium-feeling the fabric. It’s the single most useful number for describing the feel of a garment to a manufacturer.
What the GSM number decides, and what it doesn’t
The practical GSM meaning for a brand is not “heavier is better”. It is that GSM in fabric sets three things at once: how the garment drapes, what it costs, and what it costs to ship. Fabric is bought by weight, so moving a tee from 160 to 190 GSM raises the fabric cost of every unit and the freight weight of every carton — on a full container that is a real number, not a rounding error.
What GSM does not tell you is how the cloth will feel, which is why two fabrics at the same weight can be nothing alike. Yarn count, knit structure and finishing all move the handle without moving the number. That is covered further down, and it is the reason we ask for a reference garment alongside a GSM figure rather than treating the number as a complete specification.
Fabric weight chart
- 110–140 GSM
- Lightweight, drapey tees and summer styles
- 140–180 GSM
- Standard everyday t-shirts
- 180–220 GSM
- Heavyweight, premium tees with structure
- 240–280 GSM
- Lightweight sweats and mid-weight layers
- 280–350 GSM
- Standard hoodies and sweatshirts
- 350–500 GSM
- Heavyweight, structured streetwear hoodies
Common fabrics, and when to use them
- Combed cotton — soft, smooth, the everyday default for tees and basics.
- GOTS organic cotton — certified organic; the same feel with a story and documentation you can stand behind.
- Cotton fleece / French terry — the standard for hoodies and sweats; French terry is lighter, fleece is brushed and cosier.
- Modal & bamboo viscose — extra-soft, drapey, breathable; great for loungewear and intimates.
- Performance blends (poly/spandex) — stretch, moisture-wicking, and recovery for activewear.
- Recycled blends — performance or cotton-rich fabrics with recycled content for a lower footprint.
Each knit fabric, explained in full
The table above is the short version. Each of these is a fabric we knit and sew every week, and each has its own guide covering how it is made, what it costs, and where it fails:
- Jersey — the t-shirt knit, and why it curls when you cut it.
- French terry — the sweatshirt loopback, and how it differs from fleece.
- Piqué — the polo knit, how to say it, and why the collar matters more than the weight.
- Rib knit — cuffs and waistbands, and the three reasons they go slack.
- Interlock — the double knit that lies flat, and when it is not worth the extra cost.
How to choose
- Decide the feel first (lightweight summer tee vs. heavyweight hoodie), then pick the GSM.
- Heavier isn’t always better — match the weight to the garment and season.
- If sustainability matters, ask for GOTS-certified organic and see the certificate.
- Not sure? Ask for fabric swatches and a sample — feeling it beats guessing.
The fabrics, side by side
| Fabric | Typical GSM | Best for | Watch out for |
|---|---|---|---|
| Combed cotton single jersey | 140–220 | Tees, tanks, everyday basics | Shrinks if not compacted; ask for the finish |
| GOTS organic cotton jersey | 140–220 | The same garments, with documentation | Certified yarn carries its own minimums |
| French terry | 240–320 | Lighter sweats, transitional hoodies | Loops on the back can snag on rough trims |
| Brushed fleece | 280–500 | Hoodies, joggers, streetwear | Pills sooner if the base yarn is poor |
| Pique | 190–220 | Polo shirts | Collar needs interlining or it curls |
| Rib | 280–400 | Cuffs, collars, waistbands, fitted tops | Needs elastane to recover after wear |
| Modal & bamboo viscose | 140–200 | Loungewear, intimates, drapey styles | Weaker when wet; handle care instructions carefully |
| Poly/spandex performance | 180–280 | Activewear, leggings | Opacity — always squat-test before bulk |
| Recycled blends | varies | Lower-footprint versions of the above | Only credible with GRS or RCS certification |
Why two fabrics at the same GSM feel different
GSM is grams per square metre and nothing more. Three other things decide the hand, and none of them appear in the number.
The yarn.Combed ring-spun cotton has the short fibres combed out and the long ones twisted together — smoother, stronger, slower to pill. Open-end yarn is rotor-spun: faster, cheaper, coarser. A 180 GSM tee in each feels like a different price bracket. Ask which you are being quoted; a vague answer usually means open-end.
The construction. Single jersey, terry, fleece, pique and rib behave differently at identical weight. Terry has loops on the back; fleece is terry with those loops brushed into a nap; rib recovers where jersey relaxes.
The finishing.Compacting relaxes the knit and takes most of the shrinkage out before cutting. Skipping it is a common cost saving and the usual reason a cheap tee loses most of a size in the first wash. Expect roughly 3–5% residual shrinkage on a well-finished cotton tee, and ask for the measurement to be checked after wash testing rather than before.
Want help choosing for your garment? Send us your ideaand we’ll recommend a fabric and weight. Or read the manufacturing glossary.
Frequently asked questions
What does GSM mean in fabric?
GSM means grams per square metre — the weight of a fabric. A higher number means a heavier, thicker, and usually more premium-feeling cloth.
What GSM is best for a t-shirt?
Everyday t-shirts are usually 140–180 GSM. Lightweight summer tees sit around 110–140 GSM, while premium, structured tees run 180–220 GSM.
What GSM is a good hoodie?
Standard hoodies and sweatshirts are around 280–350 GSM. Heavyweight streetwear hoodies run 350–500 GSM for a thick, structured feel.
Which fabric is best for clothing?
It depends on the garment: combed or organic cotton for tees, French terry or fleece for hoodies, modal or bamboo for loungewear, and performance blends for activewear.