What Is GSM in T-Shirts? A Guide to Heavyweight Fabric

GSM in t-shirts is the number that tells you how heavy a tee is before you ever touch it. It stands for grams per square metre, and it measures the weight of the fabric across a fixed area. A fast-fashion tee usually sits around 150 to 180 GSM. A heavyweight tee starts at 220 and climbs from there. Our tees are 240 GSM, 100% cotton. Our hoodies and crewnecks are 400 GSM cotton-poly fleece.

What GSM in t-shirts actually measures

Take a one-metre-by-one-metre sheet of fabric, put it on a scale, and the reading in grams is the GSM. Higher number, denser knit, more cotton packed into the same space.

Here's roughly how it breaks down:

• 140–160 GSM: summer basics, promotional tees, the shirts that come free with something else. Light, cheap, see-through in strong light.
• 180–210 GSM: your average mall-brand tee. Fine, forgettable, thins out after a few months.
• 240 GSM and up: heavyweight territory. Structured, opaque, built to hold a shape and a print.

The jump from 180 to 240 doesn't sound like much on paper. On your body it's the difference between a shirt that hangs off you and one that sits where it's supposed to.

Why 240 GSM feels and lasts different

A denser knit does three things a thin tee can't.

It drapes with weight. Instead of clinging to every line, heavier cotton falls in a clean vertical line off the shoulders. That's what makes an oversized cut read as intentional rather than baggy. Thin fabric on an oversized pattern just looks like a shirt two sizes too big.

It's opaque. No shadow of whatever's underneath, no show-through under a shop's white lights, no going translucent in the sun. A dense weave also holds ink flat and sharp. On thin cotton the print sinks in, cracks early, and fades unevenly. On 240 GSM it stays crisp wash after wash.

It survives your laundry. Fast-fashion tees pill at the collar, stretch out at the neck, and go limp by the tenth wash because there's barely any fabric to begin with. A heavyweight tee keeps its structure. The collar stays tight, the body keeps its shape, and it earns that faded, lived-in look instead of falling apart. You can build a rotation of heavyweight graphic tees that still look right a year in.

Does heavyweight cotton work in Indian weather?

Fair question, and the honest answer is yes, with one catch. GSM measures weight, not heat. What decides how a tee breathes is the fibre and the knit, not the number.

Our tees are cotton, and cotton pulls sweat off your skin and lets it evaporate. A well-knit 240 GSM cotton tee breathes far better than a thin polyester blend at 160, even though the polyester weighs less. The blend traps heat and holds smell. Cotton doesn't.

The move for an Indian summer is simple: go oversized. A heavier tee with room in the cut keeps the fabric off your skin, so air moves underneath and the weight never feels like a blanket. That's why our fits run boxy on purpose. Come monsoon and winter, the same tee earns its keep, layering under a jacket or standing alone on a cooler night without going flimsy. You wear it ten months of the year, not just in December.

What to look for before you buy

GSM is the headline number, but read the rest too:

• The number itself: anything under 200 is lightweight, whatever the label calls it. 240 and up is the real thing.
• Fibre: cotton or a cotton-heavy blend breathes. High-polyester fabric at any GSM will trap heat.
• The cut: heavyweight only works oversized. A slim heavy tee feels stiff; a boxy one feels structured.
• The print: dense fabric holds ink better, so check that the graphic looks solid, not soaked in.

Every Conveyor Apparel tee is 240 GSM, oversized, and printed to order in India, so it ships pan-India, with most orders arriving in 5 to 9 business days. Hoodies and crewnecks are 400 GSM cotton-poly fleece. That's the trade for a tee that outlasts three of the cheap ones. To see how the weight sits under a design, any piece in the latest drops is an easy place to start.