How to tell a shirt is polyester before you buy it (60-second checklist)

You cannot touch an online shirt. That is the whole problem: the single most important fact about how a shirt will feel — what it is made of — is exactly the one a photo cannot show. The listing gives it away anyway. Here is the checklist we would use on any store, including ours.

1. Find the fibre line. A number and a word — or a red flag

Somewhere in the specs there should be a line like "100% cotton" or "95% polyester, 5% spandex". If you cannot find a fibre line at all, assume polyester: nobody who prints on real cotton forgets to mention it.

2. Translate the adjectives

Marketing English has a precise grammar here:

• "Cotton feel", "cotton touch", "cotton-like", "peached finish" — polyester. If it were cotton, the label would say cotton, not compare itself to it.
• "Microfiber", "silky smooth", "quick-dry", "moisture-wicking" — polyester, and proud of it. Fine for the gym, not what you asked for.
• "Soft blend" without percentages — a blend of unspecified things, dominated by whichever is cheaper. That is not cotton.

3. Apply the sublimation rule

If the print covers the whole garment and the store's method is sublimation (or "dye-sub", or the product is called an "AOP tee" in a marketplace), the shirt is polyester — not because the seller is hiding it, but because sublimation dye only bonds to synthetic fibre. There is no such thing as a sublimated cotton shirt. The exceptions print cotton a different way: reactive dye, which bonds to cellulose instead.

4. Read the care label like a chemist

"Do not iron", "do not tumble dry", "cool wash only, print may crack or peel" — instructions that protect a plastic layer sitting on the fabric. Dyed fibre does not need protecting; its wash rules are boring.

5. Look for sheen in the photos

Polyester filament reflects light with a slight technical shine, especially in folds; spun cotton takes light in and stays matte. Once you have seen the difference you cannot unsee it — though photos alone should never overrule the fibre line.

6. Check the price against physics

A $12–18 all-over shirt is sublimated polyester with near certainty: the economics of printing, cutting and sewing natural fabric do not fit under that price. Cotton all-over lives in premium-tee territory. A high price proves nothing — but an impossibly low one does.

7. When in doubt, ask one question

"What is the fibre content and the print method of this exact item?" A seller printing on cotton answers in one line, happily. Vague answers are an answer too.

What the checklist says about us

Run it on our shirts and here is what you should find, stated plainly so you can hold us to it: 100% cotton kulirka, reactive print — the dye bonds with the fibre, the garment is cut and sewn to order from printed fabric, and the care rules are ordinary because there is no print layer to baby. If a listing of ours ever fails its own checklist, write to us.