The ones people actually use, what changes in each, and how to get there without snapping a string along the way.
From the sixth string (the thickest) to the first:
| Tuning | 6th | 5th | 4th | 3rd | 2nd | 1st |
|---|---|---|---|---|---|---|
| Standard | E | A | D | G | B | E |
| Drop D | D | A | D | G | B | E |
| Double drop D | D | A | D | G | B | D |
| DADGAD | D | A | D | G | A | D |
| Open G | D | G | D | G | B | D |
| Open D | D | A | D | F♯ | A | D |
| Open C | C | G | C | G | C | E |
| Half step down | E♭ | A♭ | D♭ | G♭ | B♭ | E♭ |
| Whole step down (D standard) | D | G | C | F | A | D |
It only lowers the sixth string by a whole step. In return, the three low open strings form a fifth plus its octave, so you can play a power chord with one finger and slide it all over the neck. That's why half of rock and all of metal use it. Everything you knew in standard still works on the other five strings.
Open, it sounds a Dsus4: neither major nor minor, so it works equally well for both and lets notes ring against each other. It was born in Celtic modal music and ended up in folk, acoustic rock and film scores. It's the richest one on this list and the one that changes your playing the most.
The open strings already form a full major chord. With a one-finger barre (or a slide) you have every major chord on the neck, which is exactly what bottleneck blues needs. Open G is the Rolling Stones tuning —Keith Richards also takes off the sixth string and plays with five—; open D is the tuning of much of the Delta blues.
The relationships between the strings don't change: everything you know works exactly the same, it just sounds lower. There are two reasons to do it: so the voice can reach the notes more easily, and because with less tension the string is easier to bend. Hendrix, Guns N' Roses and Stevie Ray Vaughan all did it (Vaughan also used heavy strings to win back the lost tension).
Includes these tunings plus those for bass, ukulele, violin and many more instruments, each with its notes and frequencies. Every string turns green once it's within ±5 cents, and it detects on its own which one you're playing. Free, no account, works offline.
Get it on Google Play Download on the App StoreLowering a string carries no risk. Raising one does, and it's the first and second strings that break. Check the chart before you start: in drop D, DADGAD, open G and open D everything goes down —which is why they're the easiest to try—, whereas open C raises the second string from B to C. Rule of thumb: if a tuning asks you to raise a string, do it slowly and in two or three passes, letting it settle in between.
Changing tuning changes the total tension on the neck, and the neck responds by bending slightly. In practice: tune twice. Once all six strings are on their new notes, start again from the sixth and you'll see that none of them is exactly where you left it.
Just as in standard tuning: if you overshoot the note, loosen below it and bring it back up, so the string ends up with the same tension on both sides of the nut. There's more detail in how to tune a guitar.
A whole step down, a regular set goes slack: the string vibrates wider, buzzes against the frets, and the note goes sharp when you fret hard. A heavier gauge fixes it —at the cost of a truss rod adjustment if the change is big—. The reverse applies too: if you raise the tuning permanently, a lighter gauge avoids straining the neck.