Boardshorts Fabric Weight (GSM) and Stretch Guide
Published: 2026-02-01
Fabric weight and stretch are the two specifications that most affect how a pair of boardshorts feels, lasts and sells. This guide explains GSM, stretch levels and the fabric builds commonly used for men's and boys' boardshorts.
What Is GSM?
GSM (grams per square meter) measures fabric weight. Higher GSM means a heavier, denser, more durable fabric; lower GSM means lighter and cooler. For boardshorts, the usable range is roughly 100–220 GSM, and the right choice depends on use.
- 100–130 GSM — very light, fast-dry, good for kids' shorts and hot-climate casual swim trunks. May feel thin for technical surf use.
- 130–160 GSM — the sweet spot for most casual boardshorts and swim trunks: light enough to dry fast, substantial enough to drape well.
- 160–220 GSM — heavier, more premium and more abrasion-resistant; common in high-end surf boardshorts and printed styles that need to hold shape.
Stretch: 2-Way vs 4-Way
- No stretch / mechanical stretch — plain-woven quick-dry fabric. Cheapest, dries fast, fine for casual swim trunks.
- 2-way stretch — stretches in one direction, often the width. Moderate comfort and cost.
- 4-way stretch — stretches in both directions. Best for surfing and active use, where the short must move with the body. Requires spandex (elastane), usually 8–20%.
Common Fabric Builds
- Polyester-spandex — the value workhorse; best base for sublimation/all-over print.
- Nylon-spandex — softer, more abrasion-resistant, slightly more premium; common in surf boardshorts.
- Recycled polyester — same performance as virgin polyester with a sustainability story; can be GRS-certified.
Finishes Worth Specifying
- Quick-dry / moisture-wicking — essential for all swim styles.
- Chlorine resistance — important for pool and training use.
- UPF50+ — sun protection, especially for kids' boardshorts.
- Water repellent (DWR) — optional; makes water bead off and the short dry faster.
How to Specify Fabric to Your Factory
Give your factory a target GSM range, the stretch type you need, the fiber mix and any finishes. Then always confirm with a fabric swatch and a sewn sample — GSM and stretch numbers describe the fabric, but only a sample shows how it actually performs in the water.
Frequently Asked Questions
Most boardshorts use 130–160 GSM. Lighter 100–130 GSM suits casual swim trunks and kids' shorts; heavier 160–220 GSM suits premium, abrasion-resistant surf boardshorts.
For surfing and active use, 4-way stretch gives the best freedom of movement. For casual swim trunks, no stretch or 2-way stretch is usually sufficient and cheaper.
Nylon-spandex is generally the most abrasion-resistant, which is why it is common in high-end surf boardshorts. Polyester-spandex is the best value and the best base for printed designs.
Yes. Recycled polyester offers similar performance to virgin polyester and can be GRS-certified, giving your brand a documented sustainability claim.
Ready to Produce Your Own Boardshorts?
Tell us your design, target market and quantity — we will help you plan production with flexible MOQ.
Get a Free Quote