GSM is one of the most important specifications in apparel manufacturing. Yet many buyers ordering clothing for the first time do not fully understand what it means, how to specify it correctly or how it affects the cost and quality of their product.

What Does GSM Stand For?

GSM stands for grams per square metre. It is the standard measurement of fabric weight — how heavy one square metre of the fabric is in grams. A higher GSM means heavier, thicker, denser fabric. A lower GSM means lighter, thinner fabric.

GSM applies to all fabric types — jersey, fleece, French terry, pique, interlock and woven fabrics. It is used universally in apparel manufacturing and is the standard way to specify fabric weight in purchase orders, tech packs and quality control documents.

Why GSM Matters

GSM affects three things that matter directly to your brand:

GSM Guide by Product Category

T-Shirts

Hoodies and Sweatshirts

Polo Shirts

Loungewear

How to Specify GSM in Your Order

Always specify GSM explicitly in your tech pack or purchase order. Do not leave it to the manufacturer's discretion — they will default to the most cost-effective weight for them, which may not match your quality expectations.

If you are unsure which GSM to specify, request samples in two different weights and compare the hand feel before committing. A good manufacturer will offer this as part of the pre-production sampling process.

Always request a weight confirmation on pre-production samples. Manufacturers sometimes substitute lighter fabric to reduce cost. A lab test of your sample will confirm the actual GSM matches your specification.