Blue Moon by Richard Rodgers

Overview

Key: E♭ major · Chords used: 13 · Sections: 10

Form: Intro → A Section → A Section → B Section → A Section → B Section → A Section → Tag → Tag → Tag

Where these chords come from: a chord chart of this song written by a musician and shared on the iReal Pro forums, archived in the iReal Pro forum charts archived in ChoCo (de Berardinis et al., 2023). It's one musician's reading of the song, not a transcription checked against the recording. This page shows that chart as-is: the analysis below is generated directly from it by code, not written by AI. Consecutive repeats of a chord are shown once, and the piano voicings are our playable arrangement of each chord symbol, not a note-for-note transcription.

Section by section

Intro

• E♭ – Cm7 – Fm7 – B♭7 (×2)
  I – vi7 – ii7 – V7

A Section 1

• E♭ – Cm7 – Fm7 – B♭7 (×4)
  I – vi7 – ii7 – V7

A Section 2

• E♭ – Cm7 – Fm7 – B♭7 (×4)
  I – vi7 – ii7 – V7
• E♭6
  I6

B Section 1

• Fm7 – B♭7 – E♭6 (×2)
  ii7 – V7 – I6
• A♭m7 – D♭7 – G♭maj7 – G♭6 – B♭7 – F7 – B♭7
  iv7 – bVII7 – bIIImaj7 – bIII6 – V7 – II7 – V7

A Section 3

• E♭ – Cm7 – Fm7 – B♭7 (×3)
  I – vi7 – ii7 – V7
• E♭ – Fm7 – B♭7
  I – ii7 – V7

B Section 2

Same chords as B Section 1.

A Section 4

• E♭ – Cm7 – Fm7 – B♭7 (×3)
  I – vi7 – ii7 – V7

Tag 1

• E♭ – Cm7 – Fm7 – B♭7
  I – vi7 – ii7 – V7

Tag 2

Same chords as Tag 1.

Tag 3

• E♭ – Cm7 – Fm7 – B♭7 – E♭7 – A♭ – B7/A – B♭7 – E♭ – E♭7
  I – vi7 – ii7 – V7 – I7 – IV – #V⁴₂ – V7 – I – I7

Chord vocabulary

Chord	Roman numeral	Role	Heard in
E♭	I	Home chord (tonic)	Intro, A Section, Tag
Cm7	vi7	In the key	Intro, A Section, Tag
Fm7	ii7	In the key	Intro, A Section, B Section, Tag
B♭7	V7	In the key	Intro, A Section, B Section, Tag
E♭6	I6	Home chord (tonic)	A Section, B Section
A♭m7	iv7	Borrowed from E♭ minor	B Section
D♭7	bVII7	Borrowed from E♭ minor	B Section
G♭maj7	bIIImaj7	Borrowed from E♭ minor	B Section
G♭6	bIII6	Borrowed from E♭ minor	B Section
F7	II7	Secondary dominant (V/V)	B Section
E♭7	I7	Secondary dominant (V/IV)	Tag
A♭	IV	In the key	Tag
B7/A	#V⁴₂	Outside the key (chromatic)	Tag

Harmonic highlights

• A♭m7 (iv7) is borrowed from the parallel key, E♭ minor.
• D♭7 (bVII7) is borrowed from the parallel key, E♭ minor.
• G♭maj7 (bIIImaj7) is borrowed from the parallel key, E♭ minor.
• G♭6 (bIII6) is borrowed from the parallel key, E♭ minor.
• F7 acts as V/V: it resolves to B♭7.
• E♭7 acts as V/IV: it resolves to A♭.

Sources & accuracy

• Chords: the iReal Pro forum charts archived in ChoCo (de Berardinis et al., 2023). Community chord chart “Blue Moon (Nat King Cole)” (credited “Richard Rodgers-Lorenz Hart (Nat King Cole)”, style Medium Swing) from the forum file linked here, CC BY 4.0 via ChoCo. Performer/songwriter confirmed from Wikidata.
• Section names: from the chart's own markings: section names written on the chart (Intro, Verse, Chorus…) are kept, and rehearsal letters are shown as “A Section”, “B Section” and so on (the B of an AABA song is called the Bridge).
• Cross-check: the iReal Pro forum charts archived in ChoCo (de Berardinis et al., 2023). Community chord chart “Blue Moon” (credited “Rodgers Richard”, style Medium Swing) from the forum file linked here, CC BY 4.0 via ChoCo. Performer/songwriter confirmed from Wikidata. A separately posted chart of the same song; its chords match this page's closely when both are read in the same key (similarity 61%).
• Chord charts are often written in a key that suits a particular singer or band, so this may not be the key of the original recording.
• The chart's D.S./D.C./coda jumps have been written out in playing order.
• About the song: Wikipedia.
• Verified: two community charts of this song, posted in different forum threads, agree on its harmony. They're still charts, not transcriptions checked against the recording.
• Rhythm and chord durations aren't shown; each step is one chord change.