100% cotton. Length from shoulder to hem: 24 in. Width across chest: 15 in. Note: This shirt does NOT fit like a large (14-16). It fits more like an extra small (2-4). It was not oversized on my skinny 17-year-old body when I first bought it but it has shrunk in the dryer a little. However, the graphic is still clear and vibrant with only the slightest signs of wear (see photos).