EADG

EADG is a sequence used to describe the tuning of four-string instruments, consisting of the open strings tuned to the notes E, A, D, and G in ascending pitch. The same four-letter sequence is also used to denote the open strings of the lowest four strings on a standard six-string guitar, as well as the four strings on a standard four-string bass guitar, with the specific octaves determined by the instrument.

On a standard six-string guitar, the open strings from lowest to highest are E2, A2, D3, G3, B3, and E4, so the four lowest strings aligned as EADG tune to E2–A2–D3–G3. On a standard four-string bass guitar, the four strings are tuned to E1, A1, D2, and G2. A defining feature of the EADG tuning is that adjacent strings are a constant interval of a perfect fourth, which provides regular, repeatable fingering patterns across the fretboard.

Practical use of EADG as a baseline makes it common in instructional materials and in genres such as rock, pop, jazz, and folk. Its regular fourths interval simplifies learning scale shapes, chord voicings, and transposition across strings, and it serves as a convenient reference for both beginner and experienced players.

Variations and related tunings exist that modify one or more strings, such as drop tunings or open tunings built from the EADG set. Nonetheless, EADG remains a foundational reference point for many players working with four-string instruments and the lower four strings of the guitar.