Western dress codes are a set of dress codes detailing what clothes are worn for what occasion. Conversely, since most cultures have intuitively applied some level equivalent to the more formal Western dress code traditions, these dress codes are simply a versatile framework, open to amalgamation of international and local customs. This versatility has made this scale of formality a practical international formality scale.

Classifications are divided into formal wear (full dress), semi-formal wear (half dress), and informal wear (undress). Anything below this level is referred to as casual wear, although sometimes in combinations such as "smart casual" or "business casual" in order to indicate higher expectation than none at all.