Fabric weight converter
GSM to oz conversion for fabric weight: GSM is grams per square metre, and oz per square yard is what most US buyers still order in. Same mass, two units.
What GSM means on a quote
GSM is grams per square meter (g/m²): the mass of one square meter of cloth. It is the fabric-weight field on a purchase order, and the same mass that most US buyers still order in as oz/yd². A GSM number only means something next to its stage — greige, after preparation, or finished. Finishing moves the number, so write down which one you are buying.
1 oz/yd² = 33.906 GSM (g/m²) · 1 GSM = 0.0295 oz/yd²
75 GSM = 2.21 oz/yd² · 100 GSM = 2.95 oz/yd² · 110 GSM = 3.24 oz/yd² · 200 GSM = 5.90 oz/yd²
Usual 30–400. Limit 1–2000.
grams / m²
110
ounces / yd²
3.24
GSM ≈ oz/yd² × 33.906. Freeze one primary unit on the PO so rounding is not a dispute.
What is GSM?Usual 0.3–4. Limit 0.01–20.
Calculated GSM
110
| Value | GSM | oz/yd² |
|---|---|---|
| Sheer / very light | 30–70 | 0.9–2.1 |
| Light / shirting-weightIn this band | 80–120 | 2.4–3.5 |
| BeddingIn this band | 90–180 | 2.7–5.3 |
| Curtains | 120–250 | 3.5–7.4 |
| Upholstery | 200–400 | 5.9–11.8 |
Grams per square meter to oz/yd²
The factor on trade sheets is 33.906: one oz/yd² is 33.906 g/m². The figures below are the same ones in the glossary guide, so the two pages cannot disagree.
| GSM (g/m²) | oz/yd² |
|---|---|
| 30 | 0.88 |
| 40 | 1.18 |
| 50 | 1.47 |
| 60 | 1.77 |
| 80 | 2.36 |
| 100 | 2.95 |
| 110 | 3.24 |
| 120 | 3.54 |
| 140 | 4.13 |
| 160 | 4.72 |
| 180 | 5.31 |
| 200 | 5.90 |
| 220 | 6.49 |
| 250 | 7.37 |
| 280 | 8.26 |
| 300 | 8.85 |
| 330 | 9.73 |
| 400 | 11.80 |
| 500 | 14.75 |
| 600 | 17.70 |
Use the table as a quick reference, and keep one primary unit on the PO with the other as the converted figure.
The conversion formula
Multiply or divide by 33.906, and do not mix up ounces per square yard with ounces per cubic yard. A roll's total weight also needs the width.
oz/yd² = GSM ÷ 33.906
GSM = oz/yd² × 33.906
GSM (100 cm² circular cutter) = Sample Weight (g) × 100
GLM (g per linear metre) = GSM × Cuttable Width (m)
How to calculate woven GSM from yarn denier and thread density
On waterjet looms weaving continuous polyester filament, areal weight follows directly from warp ends, weft picks, yarn denier (g per 9,000 m), and weave crimp:
GSM ≈ ((EPI × Warp Denier + PPI × Weft Denier) ÷ 9,000) × 39.37 × (1 + Crimp %)
GSM ≈ ((Ends/cm × Warp Denier + Picks/cm × Weft Denier) ÷ 90) × (1 + Crimp %)
Worked example (75D × 150D peachskin bedding base at 44 ends/cm × 28 picks/cm, 5% crimp): Warp = (44 × 75) ÷ 90 = 36.67 g/m² · Weft = (28 × 150) ÷ 90 = 46.67 g/m² · Loom-state greige = 83.34 × 1.05 ≈ 87.5 GSM. After scouring, dyeing, and stenter width shrinkage (160–330 cm greige → 150–315 cm finished), finished weight settles around 95–100 GSM.
Typical polyester home-textile GSM ranges by mill program
Reference weight bands woven and finished on Weaverine's 650+ waterjet looms across 150–315 cm finished widths:
| Mill program | GSM (g/m²) | oz/yd² | Typical yarn construction | Finished width |
|---|---|---|---|---|
| Voile, sheer & pongee lining | 55–75 | 1.62–2.21 | 50D×50D – 75D×75D | 150–315 cm |
| Brushed peachskin bedding | 75–110 | 2.21–3.24 | 75D/72F × 150D/144F | 160–315 cm |
| Washed-cotton finish sheeting | 90–120 | 2.65–3.54 | 75D×150D – 100D×150D | 240–300 cm |
| Hospitality satin stripe (dobby) | 110–140 | 3.24–4.13 | 75D×150D / 150D×150D dobby | 240–315 cm |
| Contract upholstery & C6 stain-resistant | 120–180 | 3.54–5.31 | 150D×150D – 300D×300D | 150–280 cm |
| Dimout & 3-pass blackout drapery | 180–280 | 5.31–8.26 | 75D + 300D black weft + 75D | 280–315 cm |
What a GSM number does not tell you
The number says nothing about quality, hand, or drape. A 110 GSM greige in a loose, heavy construction can weigh the same as 110 GSM in a plain lightweight one. Put denier, yarn count, weave, and width on the same spec line, and freeze the stage.
Common questions
- Which conversion factor is this?
- 33.906, the factor on mill sheets. Freeze one unit on the PO.
- How do I get GSM from a cutter?
- Weigh a 100 cm² piece in grams and multiply by 100. Not a lab certificate.
- How to calculate fabric weight (GSM) from warp and weft yarn denier?
- For woven polyester filament fabric on waterjet looms, approximate loom-state GSM = ((EPI × Warp Denier + PPI × Weft Denier) / 9,000) × 39.37 × (1 + Crimp %), where EPI/PPI are ends/picks per inch, and filament crimp typically ranges from 3% to 6%.
- Why does fabric GSM change between loom-state greige and finished cloth?
- Wet finishing moves GSM in two directions at once: desizing, scouring, and peaching remove 2%–5% of mass, while dyeing and stenter heat-setting narrow the fabric width by 5%–10% (for example, 160–330 cm greige to 150–315 cm finished). Because width shrinkage concentrates more threads per square metre, finished polyester cloth typically weighs 5%–12% more per square metre than its loom-state greige.
- How do you convert GSM to GLM (grams per linear metre)?
- Multiply GSM by the fabric width in metres: GLM = GSM × Width (m). A 100 GSM bedding cloth woven at 280 cm (2.8 m) wide weighs 280 grams per linear metre, whereas the same 100 GSM cloth at 160 cm (1.6 m) wide weighs 160 grams per linear metre.
Read this in Japanese: 生地の目付（g/m²）の測り方・計算 /ja/spec/weight