In music, a power chord is an interval which serves the diatonic function of a major or minor chord. It consists of two pitches or three pitches with one doubled at the octave, and thus only two pitch classes. The pitch classes are separated by a perfect fifth, or its inversion, the perfect fourth. It is sometimes notated 5, as in C5 (C power chord).

Power chords are commonly used in various forms of rock music including hard rock, metal, and punk. The power chord's prevalence in these electric guitar-based styles is likely due to two reasons:

• First, as it contains only two pitches, the power chord is the easiest chord to form on the guitar (requiring only two or three fingers) and easily movable anywhere on the neck. If the guitar is re-tuned in drop D , then its lowest strings form a D power chord already, which can be shifted up and down with a single finger.
• Secondly, the distortion essential to rock guitar tone produces a great deal of harmonic overtones that tend to produce dissonance. The power chord contains the most consonant intervals in Western music: unison, octave, perfect 5th and perfect 4th. As a result, it largely avoids the noise produced by more complex chords on overdriven guitar.

Shown are four examples of an F5 chord. The most common voicing is the 1-5 perfect fifth (A), to which the octave can be added, 1-5-1 (B). A perfect fourth 5-1 (C) is also a power chord, as it implies the "missing" lower 1 pitch, and indeed with enough distortion this lower pitch is sometimes audible. Finally, either or both of the pitches may be doubled an octave above or below (D is 5-1-5-1).

Since power chords lack a third, they are ambiguous as to mode: they are neither major or minor. However, the musical context often implies or provides a frame of reference for major or minor. For example, in the progression bVI-bVII-I, the I chord is implied to be minor by the bVI chord, and other instrumental parts may confirm this during the one chord by playing a minor third, or may contradict this by playing a major.

The first hit song built around power chords was The Kinks's "You Really Got Me" released in 1964 (Walser 1993, p.9):

Source

• Walser, Robert (1993). Running with the Devil: Power, Gender, and Madness in Heavy Metal Music. Wesleyan University Press. ISBN 0819562602.

See also

• List of major chord shapes for guitar