What the number means
When a label or product page says 12 oz or 14 oz denim, it means one square yard of that fabric weighs about 12 or 14 ounces. Outside the United States you may see grams per square meter instead. One ounce per square yard is about 34 grams per square meter, so 14 oz denim is roughly 475 grams per square meter.
Weights are usually measured before the fabric is washed. Washing and wearing take a little weight off, so a pair that has been worn for years weighs less than its label suggests.
Light, mid and heavy
There is no official split between the bands, and sellers use slightly different cutoffs. The scale below shows the rough ranges most people mean.
| Band | Roughly | How it feels | Good for |
|---|---|---|---|
| Light | About 4 to 12 oz | Soft and drapey, close to a heavy shirt fabric at the low end | Warm weather, shirts, dresses, very stretchy jeans |
| Mid | About 12 to 16 oz | The everyday range. Firm at first, comfortable after a few wears | Most year-round jeans |
| Heavy | About 16 to 24 oz and up | Stiff and sturdy, with a long break-in | Cold weather, hard wear, people who like a rugged feel |
How weight changes the feel
Heavier denim is thicker and stiffer. It holds its shape, resists wind and abrasion, and takes longer to soften. Lighter denim is softer, cooler and more flexible from the start, but it wears through faster in high-stress spots like the inner thighs.
Weight is not the only factor. The yarn, the weave and the finishing also matter. A loosely woven heavy denim can feel softer than a tightly woven mid-weight one, and stretch denim of any weight feels more flexible than rigid denim.
Weight and the seasons
- Warm weather. Lighter denim breathes better and dries faster. Wider legs also help air move.
- Year round. Mid-weight denim is the everyday choice for most people and climates.
- Cold weather. Heavy denim blocks wind and holds warmth better. Some jeans also come with a flannel lining.
Breaking in heavier denim
Heavy raw denim can feel like cardboard for the first few weeks. Wearing it often is the main way to soften it. Sitting, walking and bending put creases into the fabric where your body moves. Some people soak new raw jeans in cold water before wearing them to remove some stiffness and finish any shrinking. Check the label first, since a soak will shrink unsanforized denim. The fabrics guide explains the difference.
Choosing a weight
For a first pair of non-stretch jeans, a mid weight is the most forgiving: sturdy enough to last, soft enough to wear right away. Go lighter if you live somewhere hot or want comfort from day one. Go heavier if you want a rugged pair that develops strong fades and you don't mind a long break-in. Then use the measuring guide to pick a size.