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Fabric Weight Converter — GSM, oz/yd² & oz/linear yard
Convert between fabric weight measurement systems: GSM, ounces per square yard, and ounces per linear yard.
How We Calculate This
Conversion formulas
- GSM to oz/yd²: Divide GSM by 33.906 (the exact factor is 33.9057 = 28.349523 g/oz ÷ 0.83612736 m² per yd²)
- oz/yd² to GSM: Multiply by 33.906
- oz/linear yard to GSM: Requires fabric width. One linear yard at width W cm covers 0.9144 m × (W ÷ 100) m². Convert ounces to grams (× 28.3495), then divide by that area.
Frequently Asked Questions
GSM stands for grams per square metre. It measures fabric weight per unit area regardless of bolt width. A higher GSM means heavier fabric. As a general guide, lightweight fabrics are under 150 GSM, medium weight 150–350 GSM, and heavyweight over 350 GSM.
Oz/yd² (ounces per square yard) measures weight per unit area, like GSM. Oz/linear yard measures the weight of one yard of fabric at its full bolt width — so the same fabric will have a different oz/linear yard value depending on its width.
Oz/linear yard includes the fabric width. A 150cm wide fabric weighing 200 GSM will have more oz/linear yard than a 112cm wide fabric of the same GSM, because each linear yard contains more fabric.
Lightweight (under 150 GSM): blouses, linings, sheers. Medium (150–250 GSM): dresses, shirts, quilting cotton. Medium-heavy (250–350 GSM): trousers, jackets, canvas. Heavy (over 350 GSM): upholstery, denim, coating.
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Last updated: February 2026
All calculations are estimates. Always verify quantities before cutting or purchasing fabric.