Standard tuning is a compromise. A good one — it balances chords and scales across every key — but a compromise. Alternate tunings trade that balance for something specific: heavier riffs, one-finger chords, drones that ring like a cathedral. Retuning two strings can change what your guitar wants to play more than a new amp will.
Here are the four worth knowing first, what each is for, and the fastest safe way in and out. All of them are presets in the tuner, which knows which string you're on even when the "wrong" note is the right one.
D A D G B E. One string changes: the low E drops a whole step. Power chords become one finger across three strings, and the bottom end gets a growl standard can't reach — which is why half of rock and nearly all of grunge lives here. Try: "Everlong", "Heart-Shaped Box", "Harvest Moon".
The move: select Drop D in the tuner, pluck the low string, turn down until the needle centers on D. The other five stay put (touch them up anyway — necks flex, as our tuning guide explains).
D G D G B D. Strum everything open and you get a G major chord. Barre one finger anywhere and you get another major chord. This is the Rolling Stones tuning — Keith Richards famously removes his low string entirely — and it's the natural home of slide guitar. Try: "Start Me Up", "Honky Tonk Women", most Delta blues.
Three strings go down (low E→D, A→G, high E→D), nothing goes up, so it's gentle on the guitar. Come back to standard by tuning up — from below, always.
D A D G A D. Neither major nor minor: a suspended, open sound where melody floats over ringing drones. Celtic guitar essentially standardized on it, and "Kashmir" made it mythic. It rewards fingerstyle players who like letting strings ring into each other — pair practice with the drone player and the tuning teaches your ears intonation for free.
E♭ A♭ D♭ G♭ B♭ E♭. Everything drops a semitone; every chord shape you know still works. Bands use it for a slightly darker weight and friendlier vocal keys — Hendrix, Guns N' Roses, and most of Alice in Chains sit here. It's also kinder to a singer at the end of a long set, which is the honest reason it's everywhere.
Tunings that raise strings (Open E, Open A) add real tension — fine on lighter gauges, string-snapping on heavy ones, which is why we've listed only the down-and-neutral tunings here. And after any retune, chords need a moment: intonation up the neck shifts slightly, so if the 12th fret suddenly sounds off, that's the trade you made, not a broken guitar.