The difference between cotton, polyester, viscose, lyocell and every other fibre you will find on a clothing label — and what it means for quality, longevity and environmental impact.
Every clothing label lists fibre content by percentage. Understanding what those fibres actually are — and what they mean for quality, comfort, longevity and environmental impact — is one of the most useful skills you can have as a clothing buyer. The difference between a natural and synthetic fibre is not just technical. It translates directly into how a garment feels, how long it lasts, and what happens to it at the end of its life.
Natural fibres come from plants or animals. They have been used in clothing for thousands of years and remain the benchmark for quality, breathability and longevity.
The world's most widely used natural fibre. Cotton is soft, breathable, absorbent and durable. Quality varies enormously — Egyptian or Supima cotton is significantly softer and longer-lasting than standard cotton. Look for 100% cotton or high-cotton blends in T-shirts, shirts and casual basics. Cotton-polyester blends reduce cost but also reduce breathability and longevity.
Wool is warm, naturally breathable and odour-resistant, and regulates temperature exceptionally well. It is naturally crease-resistant and can absorb up to 30% of its weight in moisture without feeling damp. A well-made wool garment — suit, coat or knitwear — can last decades with proper care. Merino wool is the softest variety; Shetland and lambswool are warmer but coarser. Cashmere is technically a wool from cashmere goats — softer and more expensive but less durable than merino unless made to a high standard.
Made from the flax plant, linen is one of the strongest natural fibres. It is highly breathable, becomes softer with every wash, and has a natural texture that many find preferable to synthetics. Linen wrinkles easily, which is either a characteristic or a flaw depending on your view. It is an excellent choice for warm-weather clothing and lasts extremely well.
A protein fibre produced by silkworms. Silk is extraordinarily soft, temperature-regulating and strong for its weight. It requires careful handling — hand-wash or dry-clean only — but lasts well if treated correctly. Genuine silk has a distinctive lustre that synthetic alternatives cannot replicate.
Semi-synthetic fibres are made from natural raw materials — typically wood pulp or plant cellulose — but are processed chemically into a fibre. They occupy a middle ground: more sustainable than petroleum-based synthetics, but less natural than cotton or wool.
Viscose is soft, lightweight and has good drape — it is often used as a cheaper alternative to silk. However, it weakens when wet and is prone to shrinking, stretching and pilling. Longevity is significantly lower than natural fibres. The production process uses harsh chemicals and can be environmentally damaging if not managed carefully.
A significant improvement on viscose. Lyocell is produced in a closed-loop process that recovers and reuses 99% of the chemicals used. It is stronger than viscose when wet, softer than cotton, biodegradable and generally better for the environment. Lyocell and Tencel (the branded version) are the best semi-synthetic choice.
A type of rayon made from beech tree pulp. Modal is softer than standard viscose and retains its shape better through washing. It is often blended with cotton in underwear and T-shirts. Better than viscose but still less durable than natural fibres.
Synthetic fibres are made from petroleum-based chemicals. They are cheap to produce, which is why they dominate fast fashion. Their environmental footprint is significant — they do not biodegrade and shed microplastics into waterways with every wash.
The world's most widely used fibre, accounting for around 52% of global fibre production. Polyester is durable, wrinkle-resistant and holds colour well — these are its genuine advantages. However, it is not breathable, it pills over time, and it sheds microplastic fibres with every wash. A 100% polyester garment will outlast a cheap cotton one in some respects, but will never feel as good and cannot biodegrade. Recycled polyester (rPET) has a lower carbon footprint than virgin polyester and is a better choice when synthetic content is unavoidable.
Strong, lightweight and quick-drying. Polyamide is appropriate in activewear and performance clothing where these properties matter. In everyday clothing it is typically used to reduce cost. Sheds microplastics.
A cheap alternative to wool. Acrylic is significantly worse than wool in every measurable respect — it pills badly, does not breathe, does not regulate temperature and sheds microplastics prolifically. Acrylic is the lowest quality fibre commonly used in clothing. Avoid it wherever possible.
Added in small quantities (typically 2–5%) to give stretch. Elastane is a necessary component in fitted clothing and activewear. However, it degrades over time and with heat, and makes garments significantly harder to recycle. The fewer garments containing elastane in your wardrobe, the better for longevity and end-of-life options.
When buying a garment, aim for 70% or more natural fibre content. The higher the natural fibre proportion, the better the quality, comfort and longevity in almost every case. The exception is performance or activewear, where synthetics serve a genuine technical purpose.