'One Size Fits All' is a 1975 rock album by Frank Zappa and the Mothers of Invention.

The album is the tenth and last studio album of the band - the summer/fall 1974 lineup of the Mothers of Invention, with George Duke, Chester Thompson, Ruth Underwood, Tom Fowler and Napoleon Murphy Brock.

The album features one of Zappa's most complex tracks, "Inca Roads"