What Is GSM in Fabric?
GSM stands for grams per square meter, a measurement that tells you the weight of fabric. It indicates how many grams a square meter of the fabric weighs, helping manufacturers and designers assess the thickness and density of materials.
For example, a lightweight t-shirt might be made from 160 GSM fabric, while a heavy hoodie could be 320 GSM or more.
Lightweight vs Heavyweight fabric samples
Why GSM Is Important in Apparel Manufacturing
Whether you’re designing performance wear or streetwear, understanding GSM is essential:
- Comfort: Lower GSM fabrics (130–160) feel lighter and are breathable — ideal for activewear or summer clothing.
- Durability: Higher GSM fabrics (250–400+) offer strength and longevity — great for jackets, hoodies, and denim.
- Drape and Fit: Lighter fabrics fall naturally, while heavier ones give garments more structure.
- Cost Efficiency: Thicker fabrics use more material, which could increase production costs.
Fabric Weight Categories (With Examples)
To simplify your GSM decisions:
| Fabric Weight | GSM Range | Common Uses |
|---|---|---|
| Lightweight | 30–150 GSM | T-shirts, linings, underlayers |
| Mediumweight | 150–350 GSM | Hoodies, polos, uniforms |
| Heavyweight | 350+ GSM | Jackets, outerwear, winter garments |
Knowing where your garment fits in this table can help streamline your manufacturing choices.
How to Measure GSM
You can calculate GSM manually using this simple method:
- Cut a 10cm x 10cm square of fabric.
- Weigh the sample in grams.
- Multiply the weight by 100 to get the GSM.
For example, if your swatch weighs 18 grams, the fabric GSM = 18 x 100 = 180 GSM.
Or, to simplify things, just ask your fabric supplier to share GSM details — it’s a standard part of any tech pack or sourcing document.
Choosing the Right GSM for Your Apparel Line
Here’s how you can align GSM with your apparel goals:
- Hot weather wear: 130–160 GSM – perfect for moisture-wicking activewear and everyday tees.
- Year-round essentials: 200–250 GSM – ideal for sweatsuits, joggers, and mid-weight hoodies.
- Winter wear: 300+ GSM – great for thermal clothing, outer layers, and durable workwear.
If you’re not sure where to start, we offer free tech packs and mockups to help you visualize the final product.
Related Reading
Looking to build a complete apparel line?
- How to Choose the Right Fabric for Your Clothing Brand
- Understanding Printing Techniques: Screen Print vs DTF
- What Makes a Good Tech Pack?
For a deeper dive into GSM, this industry article explains fabric weight in even more detail.
Visual Reference
Here’s a fabric GSM comparison chart to help guide your sourcing decisions:
Let’s Build Your Next Collection Together
Whether you’re a fashion startup or an established sportswear label, understanding GSM helps you make smarter, more profitable decisions.
At Blanks Limited, we help you choose the right fabrics, source premium materials, and manufacture your products with no MOQ.
📞 Ready to start your collection?
👉 Contact us now or book a free call!
