
Standard guitar tuning is E A D G B E, from the lowest, thickest string to the highest, thinnest one. Spelled with octaves it is E2, A2, D3, G3, B3, E4. The two outer strings are both E — two octaves apart — which is why a correctly tuned guitar starts and ends on the same note name.
| String | Note | Octave |
|---|---|---|
| 6th (thickest) | E | E2 |
| 5th | A | A2 |
| 4th | D | D3 |
| 3rd | G | G3 |
| 2nd | B | B3 |
| 1st (thinnest) | E | E4 |

A mnemonic makes the order stick: Eddie Ate Dynamite, Good Bye Eddie. Read it from the low E up to the high E and you have the whole tuning.
The intervals are mostly perfect fourths — E to A, A to D, D to G are each a fourth apart — which keeps chord shapes consistent across the neck and the stretch playable. The exception is G to B, a major third. That single narrower gap is what makes common chord and scale shapes fall under the fingers the way guitarists expect; it is a deliberate compromise, not an accident.
The reliable way is a tuner that listens through your microphone, detects the note you play, and shows whether the string is flat, in tune, or sharp on a cents meter. Play one open string at a time, turn the tuning peg until the needle sits at center, and move to the next.
Once you know standard, alternates are easy to describe as changes from it.
| Tuning | Notes | Change from standard |
|---|---|---|
| Drop D | D A D G B E | Low E down a whole step to D |
| Half step down | Eb Ab Db Gb Bb Eb | Every string down one semitone |
| Open G | D G D G B D | 6th, 5th and 1st lowered |
| DADGAD | D A D G A D | Low E, B and high E altered |
After you are in tune, a chord finder shows how any chord sits across these six strings.
From the lowest, thickest string to the highest, thinnest: E, A, D, G, B, E. With octaves they are E2, A2, D3, G3, B3, E4. The two outer strings are both E, two octaves apart.
Most string pairs are tuned a perfect fourth apart to keep the stretch playable and chord shapes consistent. The G-to-B major third is a deliberate compromise that makes common chord and scale shapes fall naturally under the fingers.
Use an online microphone tuner. It listens through your microphone, detects the note you play, and shows whether each string is flat, in tune, or sharp on a cents meter — no download needed.
Drop D lowers only the lowest string from E to D, giving D A D G B E. It makes power chords playable with one finger on the low strings and is common in rock and metal.