A capo (short for capodastro, capo tasto or capotasto [kapoˈtasto], Italian for "head of fretboard"; Spanish: cejilla or capodastro; French: capodastre; German: Kapodaster; Portuguese: capodastro, Serbo-Croatian: kapodaster) is a device used on the neck of a stringed (typically fretted) instrument to shorten the playable length of the strings, hence raising the pitch. It is a common tool for players of guitars, mandolins, banjos, and ukuleles. The word derives from the Italian "capotasto" which means the nut of a stringed instrument. The earliest known use of the term "capotasto" is by Giovanni Battista Doni who, in his Annotazioni of 1640, uses it to describe the nut of a viola da gamba. The first patented capo was designed by James Ashborn of Wolcottville, Connecticut.
Musicians commonly use a capo to raise the pitch of a fretted instrument so they can play in a different key using the same fingerings as playing open (i.e., without a capo). In effect, a capo uses a fret of an instrument to create a new nut at a higher note than the instrument's actual nut.