Short answer: wear midweight fabrics (about 180–240 g/m²) in warm weather and for layering, and heavyweight fabrics (240 g/m²+ for tees, 300 g/m²+ for hoodies and sweatpants) when you want structure and warmth. The heavier the fabric, the thicker, warmer and more shape-holding it is.
What GSM means
GSM — grams per square metre — is the weight of the fabric. It is the simplest way to compare two garments: a 420 g/m² hoodie is much denser than a 280 g/m² one. Our Fabric & Fit Guide lists the ranges in detail.
Summer: light to midweight
For hot days choose T-shirts and tanks around 160–240 g/m², breathable cotton, lyocell or mesh. A lighter heavyweight tee (240–260 g/m²) still works in summer because cotton breathes, but very heavy tees (400 g/m²+) are better kept for cooler days.
Spring and autumn: the heavyweight sweet spot
This is where heavyweight shines. A 240–300 g/m² tee holds a clean, boxy shape on its own, and a 300–360 g/m² hoodie or zip hoodie is warm enough to wear as your outer layer on mild days.
Winter: ultra-heavyweight and fleece
For cold weather look for hoodies, sweatshirts and sweatpants of 360 g/m² and up, ideally brushed fleece inside. Ultra-heavyweight pieces (400 g/m²+) feel rigid at first and soften with wear, and they layer well under a coat.
Quick guide by product
- T-shirts: midweight 180–240 g/m² for summer and layering; heavyweight 240 g/m²+ for structure.
- Hoodies and sweatshirts: 300 g/m²+ for autumn; 360 g/m²+ for winter.
- Sweatpants: 300–420 g/m² fleece for autumn and winter; lighter cotton or wide-leg styles for warmer days.
Is heavier always better?
No. Heavier fabric looks more premium and lasts longer, but it is warmer and less drapey. Choose by season and by the look you want: heavyweight for a boxy, structured silhouette; midweight for a softer drape and easy layering.
Shop heavyweight T-shirts, hoodies and sweatpants. More on fabric in What Is Heavyweight Cotton? GSM Explained.
FAQ
What GSM is best for a summer T-shirt?
Around 160–240 g/m². Lighter heavyweight tees up to about 260 g/m² are still comfortable in summer.
What GSM hoodie is warm enough for winter?
Look for 360 g/m² and up, ideally with a brushed fleece inside.
Does heavyweight fabric shrink more?
Not by itself — heat is the main cause. Wash at 30°C and tumble dry low or air-dry.
Is midweight lower quality than heavyweight?
No. Midweight is a different choice, not a lower one: it drapes more softly and layers more easily.
