Circle of Fifths Explorer
Edge types — what am I looking at?
A note is a single pitch class, like F.
A chord is several notes played together, like F major: F–A–C.
A seventh chord adds some kind of seventh above the root.
Fmaj7 means F major plus the major 7th: F–A–C–E.
F7 means F major plus the flat 7th: F–A–C–E♭. These are not the same chord.
Why does "F7" mean flat 7th? This is a notation convention. In chord symbols, a bare "7" always means the flat/minor 7th — you must write "maj7" to get the major 7th. So F7 = F–A–C–E♭, but Fmaj7 = F–A–C–E. When you see "C7" on a lead sheet, that chord contains B♭, not B.
Maj 7th notes — connect each root to the note one half-step below the octave. F → E
♭7 notes — connect each root to the note two half-steps below the octave. F → E♭
Dom 7th resolve — show where X7 wants to resolve. F7 → B♭
F → E answers: "What is the major 7th note of F?"
Fmaj7 answers: "What chord do I get when I add that note to F major?"
F7 → B♭ answers: "Where does the dominant seventh chord resolve?"
Chord Pathfinder — find the shortest path between two chords
The circle of fifths is usually taught as something to memorize. This explorer treats it more like a small machine: twelve pitch classes, repeated jumps of seven semitones, and the chords that appear when you stack notes inside a key.
Pick a key and the names start to behave like arithmetic. Relative minors sit nearby, leading-tone diminished chords mark tension, and seventh chords show their character by comparing their notes against the chord root’s own major scale.
See also: Graph Analysis — what happens when you connect every shared diatonic chord across all keys.
Intuition-first, not a complete theory text. Built through LLM collaboration: Claude developed the interactive explorer, and OpenAI Codex drafted this companion note after reviewing the page and nearby DerpleDex music posts.