GSM vs oz
GSM is grams per square metre; oz is ounces per square yard. Both measure fabric weight. To convert oz/yd² to g/m², multiply by about 33.9. To go the other way, divide g/m² by 33.9.
GSM is the metric standard used across most of the world and in specifications. Oz/yd² is common in the US and in canvas, workwear and sailcloth trades. A 10 oz canvas is about 339 g/m²; a 12 oz duck is about 407 g/m². Always confirm which unit a spec is in before quoting.
When you order from a mill
We quote in either. Send a target in oz or GSM and we will confirm the construction that hits it.