Diatonic Chords in a Major Key: The 7 Chords You

Diatonic chords are the chords built from the notes of a single scale. Every major key has seven diatonic chords (one rooted on each scale degree). Three are major, three are minor, and one is diminished. Most pop songs are built almost entirely from the diatonic chords of a single key.

The Formula

For any major key, the diatonic chord qualities follow this pattern:

• I: major (root chord)
• ii: minor
• iii: minor
• IV: major
• V: major (often dominant 7th)
• vi: minor
• vii°: diminished

Roman numerals are conventional. Uppercase = major, lowercase = minor, ° = diminished. Same pattern in every major key.

The Diatonic Chords in C Major

• I: C major (C, E, G)
• ii: Dm (D, F, A)
• iii: Em (E, G, B)
• IV: F major (F, A, C)
• V: G major (G, B, D)
• vi: Am (A, C, E)
• vii°: B diminished (B, D, F)

The Diatonic Chords in G Major

• I: G major (G, B, D)
• ii: Am (A, C, E)
• iii: Bm (B, D, F#)
• IV: C major (C, E, G)
• V: D major (D, F#, A)
• vi: Em (E, G, B)
• vii°: F# diminished (F#, A, C)

Why Pop Songs Use the Same Six

The vii° (diminished) chord is rarely used in pop because it sounds unstable and dissonant. The remaining six chords (I, ii, iii, IV, V, vi) are the workhorse vocabulary.

In G major, that's G, Am, Bm, C, D, Em. Pick any four of them and you've probably already played a hit song with that progression.

The Most Common Progressions

Three progressions account for an enormous share of pop music:

• I-V-vi-IV (the Pop Progression): in G, that's G-D-Em-C. Used in "Let It Be," "No Woman No Cry," "Don't Stop Believin'," and hundreds more.
• I-vi-IV-V (the 50s Progression): in G, that's G-Em-C-D. Used in "Stand By Me," "Earth Angel," and most doo-wop.
• I-IV-V (the Blues Progression): in G, that's G-C-D. Used in 12-bar blues, most early rock and roll, and folk standards.

Sources

Diatonic harmony is foundational. References: MusicTheory.net covers diatonic chord construction with interactive examples. Open Music Theory is a free college-level theory textbook. Berklee Online's harmony sequence treats diatonic chords as the foundation for all advanced harmony.

FAQ: Diatonic Chords Questions

What does "diatonic" mean?

Built from the notes of a specific scale, with no notes from outside that scale. Diatonic chords in C major use only the notes C, D, E, F, G, A, B.

Why are some diatonic chords minor and some major?

Because of the intervals between the notes. Building a chord on E in C major (E, G, B) gives a minor chord because the interval from E to G is a minor third. Building a chord on F (F, A, C) gives a major chord because the interval from F to A is a major third.

How do I figure out the diatonic chords in any key?

Apply the I-ii-iii-IV-V-vi-vii° pattern starting from the root. The qualities are always the same in any major key; only the chord names change.

Why are most pop songs in major keys?

Major keys sound bright and resolved, which fits the emotional intent of most pop songs. Minor keys appear in melancholy or moody material. The diatonic chord patterns work in both, with adjusted qualities for minor keys.

What chords work outside the diatonic set?

Borrowed chords from parallel keys (e.g., the bVII in major borrowed from minor), secondary dominants, modal interchange, and chromatic chords. Most of these advanced moves are still anchored to a diatonic foundation.