A mouse-sized animal with the typical weasel body shape: a long, slender body with short legs; a small, flattened head only slightly wider than the long neck; short, round ears; prominent whiskers; and small, beady eyes. The tail is very short, being less than 1/5 as long as the head and body. In summer, adults are brown above and white below, with white on the chin and toes. The tail is brown, and although there may be a few black hairs at the very tip, it lacks the prominent black tip of the long-tailed weasel. In winter, color can vary from completely brown to almost completely white. In Missouri, in the southern extent of the range, winter coats are usually brown.