Question: is a shot glass an ounce?
Answer: There is no standard size for a single shot, except in Utah, where a shot is defined as 1.0 US fl oz (30 ml). Elsewhere in the U.S., the standard size is generally considered to be 1.25–1.5 US fl oz (37–44 ml). A double shot in the U.S. may be 2 fluid ounces or more.