Quick answer: The best fabric for durable, squat-proof leggings is a nylon/spandex knit with 15–30% elastane in a tight, mid-to-heavy weight around 220–300 GSM. Nylon (ideally nylon 6,6) gives smoothness and abrasion resistance; a higher elastane percentage and heavier weight deliver compression and opacity so the fabric stays squat-proof. Poly/spandex is a good choice for hot-weather or outdoor leggings. (See our spandex glossary for terms.)

What makes leggings squat-proof

Squat-proof means the fabric doesn’t turn sheer when stretched over the body. It comes down to weight and knit density: a heavier, tightly knit fabric (220–300 GSM) stays opaque under tension, while thin single-jersey knits go see-through. Strong recovery keeps them from bagging at the knees and seat.

Fiber blend

Nylon/spandex is the go-to for compression leggings — smooth, strong and comfortable, with 20–30% elastane for high compression. Polyester/spandex (10–18% elastane) wins for hot or outdoor use thanks to better UV resistance, colorfastness and quick drying. For longevity, look for branded elastane — Lycra, creora or ROICA — which holds compression and shape far longer than generic spandex.

Weight and knit

For squat-proof, long-lasting bottoms aim for 240–300 GSM; for lighter run tights, 180–240 GSM. A warp-knit or double-knit interlock resists snags and abrasion better than light single-jersey. Add breathable athletic mesh panels where you want ventilation, and consider supplex for a soft, matte, cotton-like hand.

Care to keep compression

Wash cold, inside-out; skip fabric softener and bleach, which attack elastane; air-dry or tumble low. High heat is what ruins spandex over time, so keep leggings away from the hot dryer.

Not sure how much to buy? Our yardage guide covers leggings. Browse activewear performance knits or request a free sample to check weight and opacity before you cut.

What is the best fabric for squat-proof leggings?

A high-denier poly or nylon spandex with 4-way stretch and good compression is best for opaque, squat-proof leggings.

How do I avoid see-through leggings?

Choose a heavier weight fabric with a tight knit and test opacity with a stretch sample.

Where can I buy legging and activewear fabric by the yard?

Stretch House sells compression and activewear knits by the yard at stretchhouse.com, with free samples and worldwide shipping from New York since 2004.