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Fabric Weight Conversion Calculator
Convert between GSM, oz per square yard and oz per linear yard.
How We Calculate This
Conversion Formulas
GSM to oz/sq yd: GSM / 33.906
oz/sq yd to oz/linear yd: oz/sq yd x (width in inches / 36)
Weight Categories
Light (<100 GSM), Medium-Light (100-200), Medium (200-300), Heavy (300-400), Very Heavy (400+).
Frequently Asked Questions
GSM stands for grams per square metre. It is the most common fabric weight measurement used internationally and by most UK fabric shops. Higher GSM means heavier, thicker fabric. Quilting cotton is typically 110-130 GSM, while denim is 300-400 GSM.
Oz per square yard measures weight per unit area (independent of fabric width). Oz per linear yard measures weight per running yard of fabric, so it depends on the bolt width. Two fabrics can have the same oz/sq yd but different oz/linear yd if they have different widths.
Divide GSM by 33.906 to get oz per square yard. For example, 150 GSM / 33.906 = 4.42 oz/sq yd. This calculator handles the conversion automatically for you.
For a flowing summer dress, use 80-150 GSM (voile, lawn, rayon). For a structured dress, 150-250 GSM works well (cotton poplin, linen, ponte). Heavier fabrics (250+ GSM) suit winter dresses and more tailored styles.
Linear yard weight includes the full bolt width, so a wider fabric will weigh more per linear yard even if the GSM is the same. You need to know the fabric width to convert between oz/sq yd and oz/linear yd accurately.
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Last updated: March 2026
All calculations are estimates. Always verify quantities before cutting or purchasing fabric.