Fabric weight converter
GSM to oz per square yard (oz/yd²) converter
Type a weight in either box. Mills and tech packs quote grams per square metre; US buyers and denim mills quote ounces per square yard (oz/yd², also written OSY).
180 g/m² = 5.31 oz/yd²
- Tank top140–180 · 4.1–5.3 oz
- T-shirt, lightweight140–160 · 4.1–4.7 oz
- T-shirt, standard160–200 · 4.7–5.9 oz
- T-shirt, heavyweight220–280 · 6.5–8.3 oz
- Polo shirt (piqué)180–240 · 5.3–7.1 oz
- Leggings and sports tops (poly-spandex)200–280 · 5.9–8.3 oz
- Swimwear180–230 · 5.3–6.8 oz
- Joggers and sweatpants (French terry)260–320 · 7.7–9.4 oz
- Hoodie, mid-weight fleece280–350 · 8.3–10.3 oz
- Hoodie, heavyweight fleece400–500 · 11.8–14.8 oz
- Denim340–475 · 10.0–14.0 oz
Ranges we see across our own production. Fabric construction changes the hand feel as much as the weight, so treat these as a starting point for your tech pack.
At 180 GSM: Tank top, T-shirt, standard, Polo shirt (piqué), Swimwear.
How the conversion works
1 oz/yd² = 33.906 g/m². Divide GSM by 33.906 to get oz/yd²; multiply oz/yd² by 33.906 to get GSM.
Conversion chart
GSM to oz/yd² conversion chart
Common fabric weights converted to ounces per square yard, with the garments we usually make at each weight.
| GSM | oz/yd² | Typical garments |
|---|---|---|
| 120 GSM | 3.54 oz | Below the ranges we list |
| 140 GSM | 4.13 oz | Tank top, T-shirt, lightweight |
| 150 GSM | 4.42 oz | Tank top, T-shirt, lightweight |
| 160 GSM | 4.72 oz | Tank top, T-shirt, lightweight, T-shirt, standard |
| 180 GSM | 5.31 oz | Tank top, T-shirt, standard, Polo shirt (piqué), Swimwear |
| 200 GSM | 5.90 oz | T-shirt, standard, Polo shirt (piqué), Leggings and sports tops (poly-spandex), Swimwear |
| 220 GSM | 6.49 oz | T-shirt, heavyweight, Polo shirt (piqué), Leggings and sports tops (poly-spandex), Swimwear |
| 240 GSM | 7.08 oz | T-shirt, heavyweight, Polo shirt (piqué), Leggings and sports tops (poly-spandex) |
| 250 GSM | 7.37 oz | T-shirt, heavyweight, Leggings and sports tops (poly-spandex) |
| 260 GSM | 7.67 oz | T-shirt, heavyweight, Leggings and sports tops (poly-spandex), Joggers and sweatpants (French terry) |
| GSM | oz/yd² | Typical garments |
|---|---|---|
| 280 GSM | 8.26 oz | T-shirt, heavyweight, Leggings and sports tops (poly-spandex), Joggers and sweatpants (French terry), Hoodie, mid-weight fleece |
| 300 GSM | 8.85 oz | Joggers and sweatpants (French terry), Hoodie, mid-weight fleece |
| 320 GSM | 9.44 oz | Joggers and sweatpants (French terry), Hoodie, mid-weight fleece |
| 340 GSM | 10.03 oz | Hoodie, mid-weight fleece, Denim |
| 350 GSM | 10.32 oz | Hoodie, mid-weight fleece, Denim |
| 380 GSM | 11.21 oz | Denim |
| 400 GSM | 11.80 oz | Hoodie, heavyweight fleece, Denim |
| 450 GSM | 13.27 oz | Hoodie, heavyweight fleece, Denim |
| 500 GSM | 14.75 oz | Hoodie, heavyweight fleece |
Units
What GSM and oz/yd² actually measure
oz/yd² is not the weight of the garment
GSM and oz/yd² both measure fabric weight per area: grams in one square metre, ounces in one square yard. A “6 oz T-shirt” is cut from 6 oz/yd² fabric; the finished shirt weighs whatever its size and pattern pieces add up to.
oz/yd² is not ounces per linear yard
Some mills quote weight per linear yard: one yard off the roll at its full width, so the number grows with the width. Ounces per linear yard = oz/yd² × width in inches ÷ 36. A 180 GSM fabric (5.31 oz/yd²) on a 60-inch roll is 8.85 oz per linear yard. Check which unit a quote uses before you compare weights or prices.
Higher GSM is not better fabric
Weight tells you how much fabric sits in each square metre. Fibre, yarn count, knit or weave and finishing decide the hand feel, drape and durability, so a 240 GSM single jersey and a 240 GSM French terry wear very differently. Put the construction next to the weight in your tech pack.
Want to know how weight changes thickness, drape and fabric choice? Read our fabric GSM guide
Know the weight you want? Send it with your tech pack
Tell us the GSM, fibre and finish and we reply with matching fabric options, a sample plan and a bulk price.