Oz — ounces per square yard — is the single number that changes what denim costs, how it wears, and which season it sells in. It rises with yarn thickness and weave density, so heavier fabric consumes more cotton, runs slower on the loom, and lands at a higher price per meter. That price flows directly into your COGS.
The Weight Bands That Matter
| Weight | Reads as | Best use | Season |
|---|---|---|---|
| 8–10 oz | Shirting-weight | Denim jackets, dresses, linings | Summer / year-round |
| 10–12 oz | Light | Summer jeans, kidswear | Spring–Summer |
| 12–14 oz | Everyday | Mainstream jeans, first raw SKU | Year-round |
| 14.5 oz | The sweet spot | Raw selvedge, most B2B demand | Fall–Winter |
| 16–21 oz | Heavyweight heritage | Enthusiast brands, higher ticket | Winter |
How Weight Changes the Product
- Cost: moving from 12 oz to 14.5 oz raises fabric cost roughly 15–20% per pair before cutting.
- Comfort: heavier denim holds shape better but takes longer to soften — a 16 oz pair needs real commitment.
- Fade: heavier fabric creases more sharply, so honeycombs and whiskers develop with more contrast.
- Returns: weight surprises drive returns — a customer expecting 12 oz and receiving 16 oz will notice on day one.
The Sourcing Rule of Thumb
If you're launching one denim SKU, spec 13–14 oz: it works across seasons, suits most markets, and keeps landed cost predictable. Add a 14.5 oz selvedge version only after the core line proves itself. And always state the weight on the product page — oz weight is one of the top three search queries raw-denim buyers type before purchasing.
Verify, Don't Trust
Weight is easy to inflate on paper. When you receive a swatch, weigh a measured square yard yourself, or ask the mill for a third-party test report. The gap between a claimed 14 oz and a delivered 13.2 oz is the most common quiet downgrade in the trade.