The composition label is the most useful and least read thing on a garment. It is a short list of fibres and percentages, and it predicts more about how something will behave than the photograph does.

Here is a way to read one quickly.

Start with the first number

Fibres are listed in descending order by weight, so the first one is doing most of the work. If a jumper is 70% acrylic and 30% wool, it is an acrylic jumper with some wool in it, and it will behave like acrylic.

This single habit filters out most disappointments. A garment marketed on the presence of a good fibre often contains very little of it.

The four questions worth asking

Will it drape or will it hold a shape?

  • Drapes: viscose, modal, cupro, silk, rayon, tencel, fine wool
  • Holds shape: cotton, linen, polyester, denim, thicker wool

Trousers and structured jackets want shape. Slip skirts, wide-leg trousers and anything you want to move want drape. A drapey fibre in a structured garment reads limp; a stiff fibre in a fluid garment reads like a tent.

Will it breathe?

Natural fibres — cotton, linen, wool, silk — move moisture away from the skin. Polyester and acrylic largely do not.

This matters most in anything worn close to the body for a long day. A polyester blouse is fine for two hours and unpleasant for eight. It matters much less in an overcoat.

Will it pill?

Pilling comes from short fibres working loose and tangling at friction points — under the arms, at the sides, where a bag strap sits.

Highest risk: acrylic, wool and cotton blends with polyester, anything brushed or fluffy. Lowest risk: tightly spun long-staple fibres, smooth wovens, silk. If a knit feels soft in an unusually fuzzy way, that softness is often short fibre, and short fibre pills.

Will it survive washing?

  • Machine, no drama: cotton, linen, polyester, most acrylic
  • Cold and careful: viscose, modal, wool blends
  • Expect to hand wash or pay someone: silk, cashmere, most wool over about 40%, anything with a lining

Elastane is worth a specific note. It sits in the 2 to 5% range in most stretch garments and it is what gives them recovery. It also degrades with heat, which is why hot washes and tumble drying kill the fit of jeans and leggings faster than anything else.

Blends are not automatically worse

A common misreading is that blends are a compromise and pure fibres are always better. Not so.

  • A little elastane in denim or tailoring is a genuine improvement in comfort and recovery
  • Polyester in an outdoor coat adds water resistance and durability that wool alone does not have
  • A cotton and linen blend softens linen wrinkling while keeping most of the breathability

The blends worth being wary of are the ones where a cheap fibre dominates and an expensive one is present in a token amount. 5% cashmere in a 95% acrylic jumper changes the label more than the jumper.

A quick reference

| Fibre | Drape | Breathes | Pilling risk | | --- | --- | --- | --- | | Cotton | Low | High | Low to medium | | Linen | Low | Very high | Very low | | Wool | Medium | High | Medium | | Cashmere | High | High | High | | Silk | High | High | Very low | | Viscose | High | Medium | Medium | | Modal | High | Medium | Low | | Polyester | Low | Low | Medium | | Acrylic | Low | Very low | Very high |

Why this matters when shopping for a lower price

When you are looking for the same shape at a friendlier price, the composition label is where the real difference between two similar-looking garments shows up. Two coats can photograph almost the same and behave completely differently in wind and rain.

The useful move is to check the composition on the cheaper one before deciding it is a win. Sometimes it is genuinely the same fabric at a better price. Sometimes the saving is entirely explained by the label, and knowing which is which is the whole skill.

Viscose, modal and cupro goes deeper on the three fibres that confuse people most.