Why Guitars Are Tuned E A D G B E
Six strings: E, A, D, G, B, E. Why those six notes? Play the open strings on our piano and count the half steps between neighbours: five, five, five, four, five. Four perfect fourths and one major third, between G and B. See why fourths keep scales, chord shapes and power chords within one hand span, why the single third makes the common open chords easy to finger and puts the two E strings exactly two octaves apart, and how it all looks on the circle of fifths. Then compare the violin, viola and cello, tuned in fifths, with the double bass, tuned in fourths like the guitar's low strings. Every tuning is a compromise between hands and harmony.
In this lesson you'll
- Count the half steps between the six open strings (E2 A2 D3 G3 B3 E4): 5, 5, 5, 4, 5, four perfect fourths and one major third between G and B (lesson 3), adding up to 24 half steps, two octaves.
- Explain why guitars use fourths (a scale and chord shapes stay within one hand span; one power-chord shape works on E, A and D, lesson 15) and why one major third (easy open chords, the two E strings exactly two octaves apart), and see the strings on the circle of fifths (lesson 13).
- Compare other string tunings: violin G D A E, viola and cello C G D A, in fifths (wider gaps, fewer strings, a fifth is still reachable on a small neck); double bass E A D G, in fourths, because fifths would mean huge stretches.
Remember
Standard tuning, low to high, is E A D G B E. Between E–A, A–D, D–G and B–E there are 5 half steps, a perfect fourth; between G and B there are 4, a major third. 5 + 5 + 5 + 4 + 5 = 24 half steps: the two E strings are exactly two octaves apart (with fourths all the way, the top string would be F).
Fourths keep a scale and chord shapes within a hand span across neighbouring strings; the one major third makes common open chords (E, A, D, G, C, Em, Am) easy to finger. On the circle of fifths, E, A, D and G sit side by side, then a jump to B and one step back to E.
Violin-family instruments are tuned in fifths (violin G D A E; viola and cello C G D A): wider gaps, so fewer strings cover the range, and fingers can reach a fifth on a small neck. The double bass is so large that fifths would mean huge stretches, so it is tuned E A D G, in fourths.