The difference between denim and chambray lies in the weave itself.
Whereas denim is woven in a twill pattern, chambray is created with a square weave similar to a basic poplin or broadcloth but with the defining white weft, that distinctive horizontal thread in the weave of the fabric.
As a result, chambray has a much lighter and softer handfeel right off the loom than denim, which gives it a unique versatility.
Denim’s inherent thickness limits its use primarily to pants, outerwear, and heavier ‘workwear’ shirting, chambray is light enough to fashion into a much wider variety of pieces, including the ubiquitous and versatile chambray shirt as well as pants, ties and pocket squares.