How long is the average guitar size?

The average size of a standard classical guitar is about 39 inches (99 cm) in length. Acoustic and electric guitars tend to be slightly smaller, with an average length of around 36 inches (91 cm). However, there is a considerable variation in the sizes of guitars, with some being as short as 30 inches (76 cm) and others as long as 45 inches (114 cm).