Circle of Fifths

Circle of Fifths is a free, interactive web-based platform that visualizes key signatures, scales, and chord progressions on the circle of fifths, enabling musicians to explore tonal relationships with real-time playback. Available at circle-fifths.com.

What is Circle of Fifths?

Circle of Fifths is a free, interactive web-based tool that maps all twelve keys in perfect-fifth order. Users click any key to see its key signature, scale degrees, and functional chords, and hear playback on piano or guitar. The platform runs entirely in the browser with no sign-up required and was built by an indie developer and music enthusiast.

Key Features

• Interactive Circle Highlighting — Click any key to reveal signatures, scale degrees, and functional harmony tags; neighboring keys glow to show tonal proximity.
• Instant Playback — Hear single notes, scales, or full chords on piano or guitar directly from the circle panel.
• Key Signature & Scale Hub — Search by accidental count or tonic to find keys and prepare instrument-specific fingerings.
• Progression Generator — Input a groove or style to get classic progressions (I–V–vi–IV, ii–V–I) with substitution and tension analysis.
• Modulation Roadmap — Visualize modulation routes with shared chords and pivot strategies for key changes.
• Circle of Fourths View — Toggle to fourth-based progressions common in blues and jazz.
• Practice & Assessment Center — Quiz on key signatures, ear training drills, and composition challenges with progress tracking.
• Teacher Collaboration Workspace — Educators can annotate lessons, mark chords, assign modulation drills, and track student progress in real time.

Who is it for?

• Music students — Use the interactive circle to memorize key signatures and scale relationships through visual and auditory repetition.
• Composers and songwriters — Plan chord progressions, experiment with modulations, and hear voicings immediately.
• Teachers — Design annotated lessons, demonstrate tonal concepts live, and track student practice in a collaborative workspace.

What can you do with Circle of Fifths?

• Sight-readers — Identify key signatures and scale tones quickly by clicking a key and seeing the signature sequence.
• Arrangers — Build progression frameworks by dragging chords from the diatonic list, then export as MIDI or chord charts.
• Jazz improvisers — Study ii–V–I pathways using the Circle of Fourths view and compare tension contrasts.

How does Circle of Fifths work?

The platform guides users through a four-step workflow: (1) Locate primary and neighboring keys by tapping a key or typing a chord sequence; (2) toggle views (relative minor, parallel modes, Circle of Fourths) to compare relationships; (3) build progression frameworks from the diatonic chord list; (4) audition individual chords or loops and export MIDI, chord charts, or handouts.

Pricing

Circle of Fifths is completely free with no sign-up, ads, or login required.

FAQ

Is Circle of Fifths free to use?

Yes, the platform is 100% free with no sign-up, no login, and no ads.

What instruments does Circle of Fifths support for playback?

Playback is available in piano and guitar voicings, triggered directly from the circle panel.

Can teachers use Circle of Fifths in the classroom?

Yes, the platform includes a teacher collaboration workspace where educators can create annotated lessons, assign modulation drills, and track student progress in real time.

Does Circle of Fifths require an account?

No account or sign-up is needed. The tool runs entirely in the browser.