GSM to oz/yd² Converter | Fabric Weight Calculator
Convert grams per square meter to ounces per square yard for paper, paperboard, and fabric.
Grammage converter
Enter a non-negative value to convert.
oz/yd² ≈ GSM ÷ 33.90575
GSM and oz/yd² conversion charts
Select a value in either table to load it into the calculator. The tables round to two decimal places.
| GSM | oz/yd² |
|---|---|
| 1.47 | |
| 2.36 | |
| 2.95 | |
| 3.54 | |
| 4.42 | |
| 5.31 | |
| 5.90 | |
| 7.37 | |
| 8.85 | |
| 10.32 | |
| 11.80 | |
| 14.75 |
| oz/yd² | GSM |
|---|---|
| 33.91 | |
| 67.81 | |
| 101.72 | |
| 135.62 | |
| 169.53 | |
| 203.43 | |
| 237.34 | |
| 271.25 | |
| 339.06 | |
| 406.87 | |
| 474.68 | |
| 542.49 |
How to convert GSM to oz/yd²
GSM (g/m²) and oz/yd² both measure mass per unit area. A square yard covers 0.83612736 m² and one avoirdupois ounce weighs 28.349523125 g. Dividing the ounce mass by the square-yard area gives about 33.90575 g/m² per oz/yd².
oz/yd² ≈ GSM ÷ 33.90575
GSM ≈ oz/yd² × 33.90575
Worked examples
Convert a paperboard spec
Divide 300 GSM by 33.90575. You can record 8.85 oz/yd² on a buyer’s spec sheet and keep 300 GSM as the original value.
Read a fabric quote
Multiply 8 oz/yd² by 33.90575 to get 271.25 GSM. If the quote says only “8 oz,” confirm the area unit before converting.
Estimate the mass of one blank
A 25 × 20 cm blank covers 0.05 m². At 300 GSM, the flat material weighs about 15 g before glue, labels, or other components are added.
What to check on a packaging specification
Put supplier quotes in the same unit, then check that the figures describe the same layer or finished material.
Compare baseboard with baseboard
A 280 GSM baseboard plus an 18 GSM barrier layer totals 298 GSM, or about 8.79 oz/yd². Ask whether a quoted grammage already includes the coating and which sides are coated.
Ask for caliper and stiffness separately
Grammage describes mass. Ask for thickness in microns and, when rigidity matters, bending stiffness in the machine and cross directions. Use a finished sample to check folding and fit.
Record nominal weight and tolerance
Keep the grade, coating, original unit, nominal grammage, and supplier tolerance together on the spec sheet. Extra decimal places in a conversion do not improve material consistency.
Which ounce is on your spec sheet?
The number alone is ambiguous. Check the denominator or the product measurement before you convert.
- oz/yd²Ounces per square yard
- Use the calculator directly for material weight per unit area.
- oz/linear ydOunces per linear yard
- Divide by the roll width in yards to get oz/yd². For example, 12 oz per linear yard at 54 inches wide equals 8 oz/yd².
- ozOunces of mass
- To find the mass of a piece, multiply GSM by its area in m² to get grams, then divide by 28.349523125.
- fl ozFluid ounces of volume
- A cup marked 12 fl oz is rated by capacity. Check the supplier’s board spec for GSM.
Questions about material weight
Can I convert a paper weight quoted as 80 lb to GSM?
Ask for the paper grade and its basis sheet size. U.S. paper basis weight usually refers to 500 sheets at a grade-specific size, so 80 lb text and 80 lb cover can have different GSM values.USPS paper weight guide
Can I estimate GSM from a small sample?
Weigh the sample in grams, then divide by its area in square meters. For a 10 × 10 cm sample weighing 3 g, 3 ÷ 0.01 = 300 GSM. This is a quick estimate. For acceptance testing, agree on the sampling and measurement method with the supplier.
Does higher GSM mean better food packaging?
Suitability depends on the food, temperature, holding time, barrier, and finished construction. Compare the properties relevant to your use, then test a sample with the actual food and handling conditions.
Why does the result differ slightly from my supplier’s chart?
Some charts use 33.9 or 33.906 as a shortcut. Compare the units and rounding first. Keep the original value on the purchase spec so repeated conversions do not introduce extra rounding.