A map of keys you can actually hear
Most theory charts show you symbols and expect your ear to catch up later. This page flips that order: you pick a key, see which chords belong to it, and listen before you memorize anything.
From poster on the wall to something you can work with
The circle of fifths is the standard layout musicians use to see how keys relate—how many sharps or flats each one carries, which minor key shares the same signature as a major key, and why certain chord changes show up again and again in songs. Static PDFs and classroom posters are fine for reference, but they stop short when you want to know how Am in the key of C actually sounds next to F or G.
Here the wheel is interactive. Select a key, read the signature, audition every diatonic triad on piano, then sketch a short progression in the built-in sequencer if you want to go further. You can also export a clean PDF or PNG when you need a chart for a lesson, a cheat sheet in the practice room, or a handout that matches the clef you teach with.
See and hear the same key
Every selection lists the seven triads in that key and plays them on piano so you connect Roman numerals to sound, not just names on a ring.
Move by fifths with context
Clockwise and counter-clockwise arrows mark how signatures change. Neighboring keys are one step away—useful when you are modulating or comparing borrowed chords.
Go beyond a reference chart
The chord sequencer lets you drag diatonic chords onto a timeline, hear them in order, and export audio—closer to how you would actually use harmony in a song.
What is the circle of fifths?
At its core, the circle of fifths is a clock face for keys. Start at C major at the top—no sharps, no flats. Move clockwise and each step lands on a key one fifth higher: G, D, A, and so on. Every step adds one sharp to the signature. Walk counter-clockwise and you collect flats instead: F, Bb, Eb. That alone explains why band directors draw it on the whiteboard: it is the fastest way to answer how many accidentals a key uses without counting on your fingers. The inner ring holds relative minors. C major pairs with A minor; G major with E minor. They share the same key signature even though the tonal center feels different. Once you know that pairing, reading lead sheets gets easier—you recognize when a song is really in E minor while the chart still lists one sharp, or when a pop tune in D major borrows the iv chord from the parallel minor without changing the signature. The diagram also hints at chord relationships inside a key. Chords built on scale degrees that sit next to each other on the wheel often move smoothly in progressions (think I–IV–V in C: C, F, G). The yellow Roman numerals on our wheel mark those functions when you select a key, so you are not guessing which slice is the dominant or the submediant. What this page adds is playback. A printed chart cannot tell you whether the vi chord in Bb major feels wistful or merely correct on paper. Click it here and you get a piano voicing instantly. That matters for students who learn by ear, songwriters testing whether a detour through the relative minor works, and teachers who want a demo without opening a DAW. You can hide the outer staff ring if you prefer a cleaner view, switch clefs for your instrument, and download the diagram when you need an offline copy.
More than a lookup table
Selecting a key fills the panel below with its signature and all seven diatonic triads—I, ii, iii, IV, V, vi, and vii°—computed from standard theory. Tap any chord to hear it. That turns the wheel from a memorization aid into a sandbox for comparing keys side by side.
- Outer ring: twelve major keys with optional key-signature staves in treble, bass, alto, or tenor clef.
- Inner ring: relative minors aligned with their major partners in the same wedge.
- Piano audition for every diatonic triad in the selected key—block voicing, no login required.
- Built-in chord sequencer: drag chords from the pool onto a timeline, adjust length, set tempo, play back, and export MP3, WAV, or MIDI.
- Save sequencer sketches in your browser when you are iterating on a progression idea.
- Download a PDF or PNG of the chart—handy for lessons, rehearsals, or printing a clef-specific reference.
- Direction guides on the wheel show clockwise (sharps) and counter-clockwise (flats) at a glance.
How to use the circle of fifths
Pick a key on the wheel
Click a major label on the outer ring or its relative minor on the inner ring. The wedge highlights, key-signature staves update if they are visible, and the panel below lists the chords that naturally occur in that key. Click the same key again to clear the selection. If you are new to the layout, tap the “How to use” button on the chart for a quick walkthrough of the rings and arrows.
Read the signature and chord functions
Check how many sharps or flats the key uses—useful when you are transposing a vocal line or telling a student which scales to warm up with. The diatonic triads appear with Roman numerals. In C major you will see I (C), ii (Dm), iii (Em), IV (F), V (G), vi (Am), and vii° (Bdim). Yellow badges on the wheel itself echo those functions so you can see where each chord lives around the ring.
Listen before you memorize
Press any chord button to hear a piano voicing. Compare IV and V in the same key, or jump to a neighboring key on the wheel and notice how the same Roman numeral shifts color. Ear-first practice sticks better than staring at static notation, especially for guitarists and singers who think in shapes and syllables rather than note names.
Sketch progressions in the sequencer
Once a key is selected, scroll to the chord sequencer. Drag chords from the pool into the grid—columns play together, rows let you layer ideas. Hover the edge of a block to lengthen how long a chord rings out; the tool can sustain the bass root on longer hits. Set tempo, press play, and export audio if you want to take the idea into a practice track. This is the main difference from a poster on the wall: you are not only finding which chords belong to a key, you are hearing how they behave in time.
Who reaches for an interactive wheel
Teachers, songwriters, and self-taught players use it when a frozen chart is not enough—they need to hear the key and try a progression without opening a full production setup.
I project it in lessons. Students pick a key, hear all seven triads, then build an eight-bar sequence in the sequencer. Exporting a PDF with the bass clef staves saves me from redrawing the chart by hand.
Helen P.
High school choir director / Weekly theory classes
"I project it in lessons. Students pick a key, hear all seven triads, then build an eight-bar sequence in the sequencer. Exporting a PDF with the bass clef staves saves me from redrawing the chart by hand."
Helen P.
High school choir director / Weekly theory classes
"When I am stuck between two keys for a bridge, I click around the wheel and audition vi and IV in each option. Faster than loading a session just to test four chords."
Dev R.
Bedroom producer / Song sketching
"The relative minor ring finally clicked for me once I could hear Am against C major in the same view. I still keep a printed copy, but I send students here first."
Omar S.
Private guitar teacher / Beginner theory