Here are the two main ukulele tunings:
A D F# B
For most of my 40 years of playing the ukulele, I used the A D F# B tuning. About eight years ago I joined the Vokuleles in Chico CA. They tuned to F Bb D G. Most of their lives (these were women in their 80s) they used the G C E A tuning. A bandleader had them tune a whole step lower a few years before I joined them to accomodate their lowered singing range. When I joined them (later I became their leader when our bandleader died) I tuned down a whole step myself to G C E A. In this way I could play the familiar formations for the chords on their music but I'd actually being playing a step lower. I found, to my delight, that many songs I had trouble singing were suddenly within my range. I've been using the G C E A tuning ever since. The Vokuleles gave up the ukulele ghost in 2003 -- too many of them passed on or moved away. They had been together for 37 years. I led them for the last six. It was a real joy.
Special note to guitar players:
The ukulele is played using the same fingering patterns for chords that are used on the guitar with a few differences. To wit: The uke has only four strings. There are no bass strings. The first string, which would be the low E string on a guitar is a whole octave higher than a guitar player might expect and is the tone A (in D6 tuning). This is the same A that is on the fifth fret on the high E string of a guitar. The next string is the same as the D note on the third fret of the B string on guitar. This is the lowest note on a standard tuned uke. The third string is the F# note, same as the second fret on the high E string on the guitar. The final string on the uke, the B string is equivalent to the B on the seventh fret of the guitar's high E string.
Another way to look at is that playing the uke is like playing the guitar when you barre the seventh fret of a guitar. Only you're missing two strings and the first string is an octave higher. This arrangement enables the player to use the A string for melodic lines, and is sometimes one of the sources for the slightly out-of-tune sound of many ukes, since that string and the B string are often in unison, being only two frets away from each other in tone. The other source of lack of intonation is the physical limitation any string instrument has that has a short scale length.
Special note to singers:
Good luck. There are many more places to hide your voice when accompanied
by guitar, and many more tones to help you locate your voice. Not so with
the trebling uke. Many folks have to sing under
the uke. Traditional Hawai'ian voices languish in the throat and sing way
over the uke. If you have been singing along with guitar you may feel abandoned
when you switch to the uke. But persistence and hunting will eventually
land you in a sweet spot where it all works well and you feel great. Good
luck.
Another tuning, perhaps the original: G C E A
Same idea as ADF#B but a whole step lower. Looks to me that a third of the sheet music from the 1930's used this tuning. A tiny fraction of songs used G#G#CA# tuning. You can use a capo, I guess, but learning to play by barring with your index finger when you need to helps to facilitate an increase in your uking skills. I do not use a capo.
A CONFESSION I'm part purist. In my heart of hearts I believe the only true ukulele is the "soprano" instrument with re-entrant tuning. There was a time -- from 1887 to about 1910 -- when the only thing called a "ukulele" was an instrument the size of the braguinha with the re-entrant tuning of the rajão, minus the bass string of the rajão. This is the instrument that had earned the nomen, "dancing flea". Many musicians today play larger instruments and tune the fourth string down an octave. When they do that, I believe the instrument is no longer a true ukulele, but a spin-off. Instead of more accurately calling their instruments "guitaritas" or "treble guitars", they steal the lore of the ukulele and impose the name "soprano" on the ukulele. They do this by calling their instruments "tenor ukes", "concert ukes" or "baritone ukes".
Both the challenge and the joy of the true ukulele come from the re-entrant tuning -- a challenge because oftentimes the bass note you need to complete a melody line just isn't there, nor is the bass there to "comfort" your vocals. Most of us sing under the ukulele, not within it as we can with the guitar. But the spritefulness of the uke comes from that happy re-entrant tuning that places two high notes either close together or in unison. That is the design and aura that can be traced back to the pyramids and forward again through the Moors, Portugal, Madeira and, finally, Hawai'i. To play the larger instruments with straight, guitar-style tuning is to give up too easily, in my mind. This is not a condemnation in any way of the music or musicianship of those players who opt to play small guitars and call them ukuleles. I just think the real ukulele deserves respect for its ancestry and uniqueness of design.