Jeans are typically made from denim, which is a sturdy cotton twill fabric. Denim is made by weaving together two yarns: the warp (lengthwise) yarns are typically indigo-dyed, while the weft (crosswise) yarns are usually white. This creates the characteristic blue color of denim.

Some jeans are also made from other materials, such as cotton blends, synthetic fibers, or even leather.