"Shave and a Haircut" and the associated response "two bits" is a seven-note musical call-and-response couplet, riff or fanfare popularly used at the end of a musical performance, usually for comedic effect. It is used melodically or rhythmically, for example as a door knock.

"Two bits" is a term in the United States and Canada for 25 cents, equivalent to a U.S. quarter. "Four bits" and "Six bits" are also occasionally used, for example in the cheer "Two bits, four bits, six bits, a dollar." The final words may also be "get lost", "drop dead" (in Australia), or some other facetious expression. In the UK, it was often said as "five bob" (slang for five shillings), although words are now rarely used to accompany the rhythm or the tune.