Interactive Manual: Chords, Intervals & Emotions

A chord is a group of notes played together. The lowest note is usually the root. The root defines the name of the chord (for example, C is the root of a C major chord).

From the root, we build chords by counting steps called intervals.

An interval is the distance between two notes. We count using half-steps (semitones). One semitone is the smallest step on a piano, moving from one key to the very next.

• Minor 3rd (♭3): 3 semitones above the root
• Major 3rd (3): 4 semitones above the root
• Perfect 5th (5): 7 semitones above the root

We use formulas to build chords from intervals. Numbers mean semitone distances:

• Major chord: 1, 3, 5 → root + major 3rd + perfect 5th
• Minor chord: 1, ♭3, 5 → root + minor 3rd + perfect 5th
• Diminished chord: 1, ♭3, ♭5 → root + minor 3rd + flattened 5th
• Augmented chord: 1, 3, ♯5 → root + major 3rd + sharpened 5th

A flat (♭) means the note is shifted one semitone down. A sharp (♯) means the note is shifted one semitone up.

A double flat (♭♭) means the note is shifted two semitones down.

• 7th chord: Adds a 7th interval above the root (C7 = C–E–G–B♭)
• 9th chord: Adds a 9th interval (C9 = C–E–G–B♭–D)
• Suspended (sus2/sus4): Replace the 3rd with a 2nd or 4th
• Minor Major 7: Minor chord with a natural 7th (C–E♭–G–B)
• Half-diminished: Minor chord with a flat 5th and flat 7th

Different chords carry different moods. Here are common associations:

• Major: Bright, happy, open
• Minor: Sad, emotional, dark
• Diminished: Tense, eerie, unstable
• Augmented: Dreamy, strange, floating
• Minor Major 7: Tragic, bittersweet
• Altered Dominant (7♭9, 7♯9): Aggressive, cinematic tension
• Suspended: Open, unresolved, childlike
• Add9, add11: Fresh, modern, uplifting