Understanding Intervals

An interval is the distance between two notes. Everything in music — chords, scales, melodies — is built from intervals. Master the 13 intervals and you can decode any piece of music by ear.

The Core Idea

Every pair of notes has an interval — measured in semitones (half-steps), which correspond to frets on a guitar. The 12 notes of Western music sit in a chromatic scale; the distance between any two of them is an interval. Intervals have names, qualities (major/minor/perfect), and emotional characters.

The 12 chromatic notes — each step = 1 semitone = 1 fret

C
0
C#
1
D
2
D#
3
E
4
F
5
F#
6
G
7
G#
8
A
9
A#
10
B
11

Interval Explorer

Root note

P5

Perfect 5th

Perfect interval · 7 semitones

A
E

A + 7 semitones

Hear it:

The most powerful, open interval in Western music. Perfectly stable. Sounds massive, ancient, and universal.

Fretboard Distance — 7 frets on a single string
A
E
R
+7

Single guitar string · each cell = 1 fret = 1 semitone · R = root · +7 = interval note

Consonance

Perfect

On Guitar

Power chord = root + perfect 5th. On most adjacent string pairs: 2 frets up. The interval that drives the Circle of Fifths — go up a P5 twelve times and you return to the start.

Used In
  • Power chords (5th chords)
  • All major and minor chords
  • Circle of Fifths navigation
  • Open string drone tunings
Famous Examples
Every power chord in rock historyStar Wars main theme opening leapTwinkle Twinkle (5th leap)Gregorian chant open 5ths

All Intervals — Quick Reference

AbbrNameSemitonesConsonance
P1Perfect Unison0
m2Minor 2nd1
M2Major 2nd2
m3Minor 3rd3
M3Major 3rd4
P4Perfect 4th5
TTTritone6
P5Perfect 5th7
m6Minor 6th8
M6Major 6th9
m7Minor 7th10
M7Major 7th11
P8Perfect Octave12

Click any row to explore that interval above.

Essential Guitar Interval Shapes

These two-string patterns are the physical vocabulary of interval playing on guitar.

P5

Power chord (P5)

Root on low E → 5th on A string: same fret + 2 up. The backbone of rock and metal rhythm playing.

X
E6
R
A5
R+2
D4
×
G3
×
B2
×
e1
P8

Octave shape (P8)

Skip one string, go 2 frets up (3 frets on the G→B crossing). Classic Wes Montgomery and Hendrix technique.

R
E6
×
A5
R+2
D4
×
G3
×
B2
×
e1
M3

Major 3rd (string pair)

Adjacent strings (E-A, A-D, D-G): 1 fret back on upper string. G→B: same fret (the exception). Country double-stop lick fuel.

×
E6
R
A5
R−1
D4
×
G3
×
B2
×
e1
m3

Minor 3rd (string pair)

Adjacent strings (E-A, A-D, D-G): 2 frets back on upper string. Blues and minor key double-stop territory.

×
E6
R
A5
R−2
D4
×
G3
×
B2
×
e1

How Intervals Build Everything

Every chord is just a stack of intervals from a root note. Every scale is a sequence of intervals. Once you know your intervals, you can construct and analyze anything.

Major Chord
RRoot (1)
M3+ Major 3rd (4 semitones)
P5+ Perfect 5th (7 semitones)
Minor Chord
RRoot (1)
m3+ Minor 3rd (3 semitones)
P5+ Perfect 5th (7 semitones)
Major Scale (Ionian)
P1Root (+0 st)
M22nd (+2 st)
M33rd (+4 st)
P44th (+5 st)
P55th (+7 st)
M66th (+9 st)
M77th (+11 st)

The Guitar Tuning Exception: G→B String

Standard guitar tuning uses perfect 4ths between all adjacent strings — except between the G (3rd) and B (2nd) strings, which are a major 3rd apart. This means all fretboard interval shapes shift by 1 fret when crossing that string pair. Every guitar player has to internalize this exception; it explains why chord shapes look different depending on which strings they span.

E
P4 ↑
A
P4 ↑
D
P4 ↑
G
M3 ↑
B
P4 ↑
e

Hear intervals in action

Build chords and scales to hear how intervals stack — or explore chord theory to see how these distances create harmony.