Worsted weight yarn is a medium-weight yarn that sits in between light and bulky yarns. It is thicker than sock and sport weight and thinner than bulky weight yarn. The gauge for worsted weight yarn is roughly 5 stitches per inch on a size 7 or 8 needle. However, the needle size for worsted yarn varies depending on the project, and in general, a 4.5 to 5.5 mm (US 7-9) needle will produce a firm yet pliable fabric. When shopping for worsted yarn, look for the word "worsted" or a prominent number four on the yarn label. If both are absent, check the knitting gauge to see if it falls within 16-20 stitches for four inches of knitting.