Fabric Weight Converter (GSM ↔ oz/yd²)
Convert fabric weight between metric GSM and US oz/yd² — exact, with a t-shirt and denim weight guide.
Exact: 1 oz/yd² = 33.906 gsm. "oz" here is per square yard (the apparel/textile standard) — not linear yard, and not silk momme.
GSM vs oz/yd² — what they mean
Both measure how heavy a fabric is per unit area. GSM is grams per square metre (metric, used worldwide). oz/yd² is ounces per square yard (US). They convert exactly: 1 oz/yd² = 33.906 gsm. Higher = thicker, warmer, more durable.
Typical fabric weights
| Fabric | GSM | oz/yd² |
|---|---|---|
| Lightweight t-shirt | 120–150 | 3.5–4.5 |
| Midweight t-shirt | 150–185 | 4.5–5.5 |
| Heavyweight t-shirt | 185–220 | 5.5–6.5 |
| Light denim | ~305 | ~9 |
| Midweight denim | ~407 | ~12 |
| Heavy / raw denim | 475–543 | 14–16 |
| Canvas / duck | 300–540 | 9–16 |
These are typical ranges and vary by brand and weave — use them as a guide, not exact thresholds.
FAQ
About 5.3 oz/yd² — a solid midweight tee: not see-through, holds shape, good for printing. 120–150 gsm is light/summer, 185+ gsm is heavyweight/premium.
14 oz/yd² ≈ 475 gsm — a heavy, rigid denim. 9–11 oz is light–midweight, 16 oz+ is raw/heavy denim.
No — this tool uses oz per square yard, the standard for fabric weight. Per linear yard depends on the fabric's width, so it's a different number. Don't mix them up.
Not always — higher gsm is thicker, warmer and more durable, but also heavier, stiffer and less breathable. Pick the weight for the use: light for summer tees, heavy for jackets/bags.