What Is Swimwear Made Out Of? Here Is A Full Guide
Understanding what swimwear is made out of is the single most useful thing you can do before you buy. The right material will hold its shape through chlorine, saltwater, and sunscreen season after season. The wrong one will look tired by August.
At BERLOOK, every swimsuit is built from recycled polyamide and spandex — chosen for performance, longevity, and a dramatically lower environmental footprint. This guide explains exactly why, and what every fabric on a swimsuit label actually means.
The Main Swimwear Fabrics Explained
Modern swimsuits are almost always made from synthetic fabrics — specifically blends of two or three materials engineered to perform in water. Natural fibers like cotton absorb water heavily, lose their shape when wet, and degrade quickly in chlorine and saltwater. Synthetics are built for exactly the conditions swimwear faces.
The five fabrics you'll encounter most in women's swimwear are nylon (polyamide), polyester, spandex (also called elastane or Lycra®), PBT polyester, and — increasingly — recycled eco alternatives.
- Nylon (Polyamide/ Typical blend: 74–82% nylon / 18–26% spandex)
Soft, silky, and incredibly comfortable against skin. The go-to for fashion swimwear, bikinis, and one-pieces. Dries quickly, holds vibrant prints beautifully, and has excellent stretch and recovery. Less chlorine-resistant than polyester — ideal for beach and casual pool use. "Nylon" and "polyamide" on a label mean the same thing.
- (Typical blend: 80–90% polyester / 10–20% spandex)
The workhorse of swimwear. Highly resistant to chlorine, UV rays, and fading. Naturally hydrophobic, so it dries fast and holds its shape through repeated pool use. Slightly firmer in feel than nylon, but the top choice for frequent swimmers and active water sports.
- Spandex / Elastane / Lycra® (Usually 7–26% of the blend)
The stretch ingredient in every swimsuit. Even a small percentage delivers four-way elasticity that moves with your body and springs back to shape. Without it, a swimsuit simply wouldn't fit. Lycra® is the trademarked brand name by The LYCRA Company — spandex and elastane are the generic equivalents.
- PBT Polyester - Performance & competitive swimwear
A high-performance polyester used in competitive and athletic swimwear. Exceptionally chlorine-resistant and color-fast — it outlasts standard polyester under heavy pool use. If you train in chlorinated pools daily, look for PBT in the fabric composition.
- Recycled Polyamide (ECONYL® · REPREVE® · rPET)
Made from regenerated nylon or recycled polyester sourced from ocean waste, fishing nets, and plastic bottles. Performs identically to virgin synthetics — same stretch, softness, and durability — with a fraction of the environmental cost. The direction the entire swimwear industry is moving.
What about cotton in swimwear?
Cotton is soft and breathable, but it absorbs water heavily, takes a long time to dry, loses shape when wet, and degrades quickly in chlorine and saltwater. It works well for beach cover-ups and loungewear — not for active swimming.
Fabric Comparison: At a Glance
Not all swimsuit fabrics perform equally. Here's how the main materials compare where it matters most.
| Fabric | Softness | Chlorine Resistance | UV Protection | Best For |
|---|---|---|---|---|
| Recycled Polyamide / Spandex (BERLOOK) | High | Moderate | Moderate | Fashion, beach, casual |
| Virgin Nylon / Spandex | High | Moderate | Moderate | Fashion, beach use |
| Polyester / Spandex | Medium | High | High | Lap swimming, pool training |
| PBT Polyester | Medium | Very High | High | Competitive / daily training |
| ECONYL® (recycled nylon) | High | Moderate | Moderate | Eco beach & casual swim |
| Cotton blend | High | Low | Low | Cover-ups & lounging only |
Pro Tip:
Always check the fabric label before buying. A BERLOOK swimsuit typically reads "Recycled Polyamide 74%, Spandex 26%." The higher the spandex percentage, the more stretch and shape recovery you'll get. For pool training, look for 80%+ polyester in the blend for better chlorine resistance.
Sustainable & Recycled Swimwear Fabrics
Sustainability has moved from niche to mainstream in swimwear, and the fabric innovation happening here is genuinely impressive. BERLOOK sits at the center of this shift — our entire swimwear range is made from recycled materials, not as a trend but as a founding commitment.
Recycled Polyamide — The BERLOOK Standard
Recycled polyamide is nylon regenerated from post-consumer waste — discarded fishing nets, industrial plastic, and fabric scraps — restored to original purity. Every BERLOOK swimsuit is made from it. The performance is identical to virgin nylon: same softness, same stretch, same color vibrancy — with a significantly smaller environmental footprint.
ECONYL® — Regenerated Nylon
Some of our reversible swimwear styles feature ECONYL®, a branded regenerated nylon developed by Aquafil from ocean waste and landfill-bound nylon — fishing nets, carpet flooring, and industrial plastic — restored to virgin-quality fiber. It can also be regenerated again at end of life, making it part of a true circular system.
REPREVE® — Recycled Polyester
Made from recycled plastic bottles, REPREVE® is durable, fade-resistant, and chlorine-tolerant. Some BERLOOK styles incorporate recycled polyester blends for specific structural applications — you'll see it listed on the product label.
How to Choose the Right Swimwear Fabric for You
The best swimsuit fabric depends entirely on how and where you wear it. Here's a simple framework.
If you love the beach and casual pool days
Recycled polyamide-spandex blends — like those used across all BERLOOK bikinis and one-pieces — are your sweet spot. Soft, flattering, and vibrant through a full season of beach and casual pool use.
If you train in a pool regularly
For heavy chlorine exposure, look for polyester-spandex or PBT polyester rated as chlorine-resistant. For casual training, BERLOOK suits hold up well in pools with moderate use — just rinse immediately after each swim.
If sustainability matters to you
All BERLOOK swimwear is made from recycled polyamide. For a reversible, double-duty eco option, our ECONYL® reversible styles are a particularly strong choice — two looks, one suit, zero virgin materials.
If you need extended sizing
Our plus size collection uses the same premium recycled polyamide blends as the rest of the range — designed with the same four-way stretch and shape retention, across a wide range of styles and cuts.
What fabric weight should you look for?
Most quality fashion swimwear falls between 180–200 g/m². Lighter fabrics may lack structure or coverage. Heavier fabrics (200–220 g/m²+) are typically found in competitive or structured supportive styles. BERLOOK sits in the quality mid-range: enough weight for great coverage, light enough for all-day comfort.
How to Care for Your Swimsuit?
Even premium recycled polyamide breaks down prematurely without proper care. Chlorine, saltwater, sunscreen, and body oils all degrade fibers — but a few consistent habits can dramatically extend the life of your suit.
- Rinse immediately after every use.
Chlorine and saltwater continue breaking down fabric fibers even after you leave the water. A quick rinse in cool, clean water after every swim is the single most effective care habit — especially important for recycled polyamide after chlorine exposure.
- Hand wash only, with a mild detergent.
Machine washing — even on gentle — stretches seams and weakens elastic fibers. A gentle hand wash in cool water is all your suit needs. Avoid bleach and fabric softeners; softeners in particular break down the spandex that gives BERLOOK suits their shape.
- Never wring your suit out.
Twisting distorts and weakens fibers permanently. Instead, gently press water out between two towels, then lay the suit flat to dry in a shaded spot.
- Air dry flat, away from direct sun.
UV exposure fades color and weakens fiber structure over time. Never use a tumble dryer — heat is one of the fastest ways to destroy elastane and cause shrinking or misshaping.
- Rotate between two suits.
Alternating between two swimsuits gives each one time to recover its stretch and shape between uses. This single habit can double the effective lifespan of each piece — a great excuse to pick up a second style in the BERLOOK sale.
- Apply sunscreen before putting on your suit.
Many sunscreens — especially avobenzone-based formulas — cause yellowish staining on swimwear. Apply at least 30 minutes before putting your suit on and let it fully absorb into your skin first.
- Store dry, flat, and in a cool place.
Never pack a damp swimsuit into a plastic bag — trapped moisture leads to mould and accelerates fabric deterioration. Once completely dry, store it flat or gently folded in a cool drawer or breathable fabric bag.
Frequently Asked Questions
What is BERLOOK swimwear made of?
BERLOOK swimwear is made primarily from recycled polyamide (recycled nylon) blended with spandex — typically 74% recycled polyamide and 26% spandex for the outer fabric, and 82% recycled polyamide and 18% spandex for the lining. Some metallic and statement styles incorporate a small percentage of metallic fiber. All fabrics are chosen for performance, softness, and sustainability. Browse the full range at berlook.com.
Is nylon or polyester better for swimwear?
It depends on use. Nylon (polyamide) is softer, more flattering, and better suited to fashion, beach, and casual pool swimwear — it's what BERLOOK uses across its range. Polyester is tougher and more chlorine-resistant, making it better for frequent lap swimmers or competitive training. Neither is universally superior; they're designed for different situations.
What does "recycled polyamide" mean on a swimsuit label?
Recycled polyamide is nylon regenerated from post-consumer waste — discarded fishing nets, industrial plastic, and fabric scraps — rather than produced from virgin petroleum. It performs identically to conventional nylon in stretch, softness, and durability, with a significantly lower environmental footprint. It's the core fabric in every BERLOOK swimsuit.
What does Lycra® or spandex mean on a swimsuit label?
Lycra® is a trademarked brand name for spandex/elastane fiber — they all refer to the same material. It's the stretchy component in every swimsuit, typically making up 18–26% of the fabric blend, delivering the four-way elasticity that allows your suit to move freely and return to its original shape after wear.
Are recycled swimsuits as good quality as conventional ones?
Yes — in every measurable way. Recycled polyamide is restored to its original purity during regeneration, meaning it performs identically to virgin nylon in stretch, durability, softness, and color retention. BERLOOK's range is proof: over 2.9 million plastic bottles recycled, no compromise on quality.
How long should a quality swimsuit last?
With proper care, a swimsuit made from recycled polyamide should last multiple seasons. Rinsing after every use, hand washing only, and rotating between suits are the three habits that make the biggest difference. Check out the BERLOOK sale to pick up a second suit for rotation.
Ready to Find Your Perfect Suit?
Every BERLOOK swimsuit is made from recycled polyamide — soft, stretchy, sustainable, and built to last. Free shipping on orders over $79.
