Baritone guitars are most typically tuned to B using the same relative intervals between strings as a standard guitar. With this tuning the baritone is tuned B-E-A-D-F#-B (low to high) with string gauges .013-.018-.028-.038-.050-.070. Tuning to a fifth below (A-D-G-C-E-A) is also fairly common.
The scale lengths of baritone guitars are typically 26 to 28 inches, longer than the standard electric guitar scale length range of 24.75 (Gibson) to 25.5 inches (Fender). I have spotted baritone scale lengths as high as 30 inches, but 27 to 28 inches seems to be the most common.
What It Isn't: It is Not a Six-String Bass
Danelectro sold a six string bass in the late 1950s and Fender created a six-string bass in the 1960s called the Bass VI, both of which are often called baritone guitars. These instruments include four low strings tuned the same as a four string bass guitar (EADG) with two additional high strings (B and E). In other words, these instruments are tuned one octave lower than a standard guitar.
The scale length on these instruments is typically 30 inches, and the neck width is narrow compared to most basses. In my opinion, Bass VI style instruments should be considered a type of bass guitar, not a baritone guitar. The design intent was to make a bass that felt familiar to players of standard guitars. (Reportedly John Lennon and George Harrison used a Bass VI to play bass with the Beatles when McCartney played piano.) The baritone guitar is intended to be an instrument for the pitch range in between the standard guitar and bass. I call the early Danelectros and the Fender Bass VI "Bass VI type instruments" to distinguish them from baritone guitars.
Even the staff at Fender seem to be confused about the difference between Bass VI-style instruments and baritones. Their Jaguar baritone is described as being a Bass VI type instrument but it is tuned to B and has a 27" inch scale which makes it a baritone, not a Bass VI type instrument. In fact, Fender has a Bass XI reissue instrument available that has a 30.3" scale.
What It Isn't: It is Not a Seven String Guitar
Another instrument somewhat similar to the baritone guitar is the seven-string guitar, sometimes referred to as the seven-string baritone guitar. Modern electric seven-string guitars are most typically tuned like a standard guitar with the addition of a low B string (B-E-A-D-G-B-E). (seven-string guitars with an additional high string also exist) Scale lengths of 25.5-26 inches seem most common. Seven string guitars can be considered baritone guitars with an additional high E string and the overall sound is essentially the same.
This site will concentrate on the six-string baritone guitar, but I am sure that much of the information will also be relevant to players of seven-string guitars and six-string basses.
Your feedback and questions will guide the future of this site.
Mike 064 Freeman