How to read fabric composition: a practical shopping guide
A small label sewn into the side seam, folded in four, covered in percentages and symbols. It usually goes under the scissors, because it scratches your neck. Yet it is the only place where a piece of clothing tells the truth about how long it will last and how it will wear.
What exactly will you find on the label?
A label carries three separate pieces of information: the fibre composition in percentages, the care symbols and the country of manufacture, and only the first one says anything about quality. The composition is always listed starting with the fibre that makes up the largest share.
The order matters in practice. "70% cotton, 30% polyester" describes a completely different garment from "70% polyester, 30% cotton", even though both use the same raw materials. The first wears like cotton, the second like a synthetic.
Which natural fibres are worth recognising?
Natural fibres split into plant and animal ones, and they differ above all in how they handle moisture and whether they hold warmth. That difference decides the season in which a garment will do its job. A wider overview sits in the guide to types of fabrics.
- Cotton. It absorbs moisture and breathes, but dries slowly and stretches at the elbows. It works best in the layer closest to your skin.
- Linen. It cools more effectively than any other fibre and creases by nature, which is not a flaw. Linen and muslin belong to the warm months rather than autumn, and the same goes for linen trousers.
- Wool. It keeps you warm even when slightly damp and does not hold on to odours. It needs washing at a low temperature and drying flat.
- Viscose. Formally a man-made fibre, because it is produced from wood cellulose, but in wear it sits closer to natural ones: it drapes softly and feels pleasantly cool.
Viscose is the fibre most often misunderstood. It is not a synthetic in the way polyester is, but a fibre made from processed wood pulp, which is why viscose dresses feel entirely different to the touch from polyester ones.
Does a synthetic blend always make a garment worse?
A synthetic share of up to twenty percent usually improves durability and helps the cut hold its shape, and only above half of the composition does it start to take away breathability. Polyester on its own is not a sign of lower quality.
The table shows at which values a blend helps and when it starts to get in the way.
| Blend | How much helps | What it gives | When it harms |
|---|---|---|---|
| elastane | 2 to 5% | the garment returns to shape after wear | above 8%, the fabric starts to cling to the body |
| polyester | up to 20% | less creasing, faster drying | above 50%, breathability drops |
| polyamide | 10 to 30% | resistance to abrasion, smoothness | above 50% in knitwear, it builds static |
| acrylic | no good threshold | lowers the price, imitates wool | always in a sweater, it pills after a few washes |
The first two rows cover most of what hangs in a wardrobe. Elastane in trousers and a small amount of polyester in a shirt are blends that genuinely make wearing easier, not a manufacturer cutting costs.
Cotton with a little elastane behaves predictably in this arrangement: in daylight the weave looks even, and in movement the fabric springs back instead of bagging at the knees.
What should you check in the shop before buying?
Three questions are enough to judge a garment in the shop, with no knowledge of textile technology. Ask them in this order.
- What comes first in the composition? That fibre decides how the garment behaves. The rest only adjusts it.
- Does the season match? Linen in September will be too cool and acrylic in summer too stuffy, whatever the cut.
- Does the care fit your habits? A hand wash symbol on shirts you wear every week is a real problem, not a detail.
That third point decides whether a piece stays in rotation or drifts to the bottom of the wardrobe. Things that need hand washing are usually worn less often, however well they fit. This applies above all to knitwear, where a wool programme is often the only safe option.
What should you avoid when reading the composition?
Three assumptions come up most often, and all of them lead to poor purchases.
- Never judge quality by the name of the fibre alone. Lightweight cotton shows through and stretches faster than a good blend with polyamide.
- Avoid buying a sweater that is mostly acrylic. Pilling appears after a few washes and cannot be removed for good, while sweaters with wool last for several seasons.
- Never ignore the drying symbol. A crossed out square with a circle inside means no tumble dryer, and breaking that rule is what most often ruins a garment beyond repair.
It also pays to stop cutting labels off straight after buying. The symbols, all decoded in the guide to laundry symbols, help at the first wash, and the composition helps you judge whether the next piece from the same brand is worth buying.
What does "viscose with elastane" mean?
That the base is a cellulose fibre which gives a soft drape, while elastane lets the fabric return to its shape. It is a common composition in everyday dresses.
Is 100% cotton always a good choice?
Not always, because cotton with no blend creases heavily and stretches at the knees and elbows. In trousers and fitted dresses a small addition of elastane works better.
How do you recognise good quality when the composition looks identical?
Check the weight and the weave: hold the fabric up to the light and see whether it shows through. The same cotton in two different weights makes two entirely different garments.
What does a missing composition label mean?
That the garment does not meet the labelling requirement, so it is worth approaching with caution. When you buy online, the composition should be given in the product description, not only in a photo of the label.
Go back to that label folded in four. Three seconds spent checking the first fibre in the composition save a great deal of disappointment after the second wash. The rest of the label then becomes a set of instructions rather than a puzzle.