Ukuleles are manufactured in four common sizes or formats: soprano, concert, tenor and baritone.
Regarding tuning, the soprano, concert, and tenor ukuleles use the same in general: from fourth to first, G C E A; the baritone is tuned one fourth lower: D G B E, exactly like the first four strings of a guitar.
Sizes are defined by their scale – that’s right, the string length – and by the size of the body, which accounts for the sound quality.
When it comes to deciding on the size of ukulele, you must take into account:
From left to right: soprano ukulele concert ukulele and tenor ukulele.
The soprano, also called standard, is the original ukulele size, and it’s the smallest member of the family. Its scale – the length of the vibrating string – is between 345 and 355-mm long. The largest instrument turns out to be around 530 mm.
The concert-size ukulele is a little bigger and has a deeper tone than the soprano. Its scale is around 380 mm and it is 620-mm long. (Note: when talking about ukuleles,“concert”refers to the size, not the quality, a concert uke is not better or worse than any uke of any other type).
The tenor size follows suit to the concert model, it brings more volume and has a more complex sound. It is, in our opinion, the most appropriate instrument when using a fourth string in low-pitch. Its scale is approximately 430 mm, and its total length is approximately of 670 mm.
The baritone ukulele, even bigger, has the same tuning as the first four strings of a guitar, and, of course, it gives a deeper tone. It has a scale of 510 mm and it is 740-mm long.
So, from smaller to bigger size, we have: soprano, concert, tenor and baritone. There are also other peculiar combinations (longneck, super concert, sopranino…), but we will keep it simple and not elaborate about that.
The“appropriate”scale is the one that best adjusts to the performer’s hands. In general:
Anyway… checking out some youtube videos may help you decide on one type of ukulele or the other (especially to get what the different sounds are)
Source: Learn the Ukulele (reproduced with permission)