Some differences between a ukulele and a guitar are in their number of strings, size, chord setup, different types and origin. Although both are stringed instruments, the number of strings for a guitar is six and a ukulele has four. Guitars can have nylon or steel strings, but ukuleles usually have nylon strings.
The sizes of these two instruments are different. A standard ukulele can measure about 21 inches; a guitar's size is larger, but sizes vary among manufacturers. While the two main types of guitars are acoustic and electric, ukuleles are available according to sizes and tones that include soprano, alto, tenor and baritone. The soprano is the smallest ukulele.
Another difference is that the chord setup is simpler for an ukulele. The origins and history of these two instruments is that the ukulele is associated with Hawaii, and the guitar comes from Spain.