HarmoniConnect your chords without thinking
Optimal voice leading, calculated automatically: the most natural transitions between your chords, no thinking required.
Available on iPhone and Android · One-time payment, no subscription.
No more jumpy chords
Without voice leading, every chord restarts from its root position. Your hands jump, the ear loses the thread. HarmoniKeys smooths the path.
Every chord played in root position: your fingers leap from one end of the keyboard to the other.
The algorithm picks inversions and positions for minimal movement. The link between chords becomes obvious.
How it works
From chart to performance, HarmoniKeys handles the harmonic math for you.
Enter your chart
Type in your chords or load a classic progression: Canon, Blues, Jazz, Pop.
The algorithm optimizes
HarmoniKeys computes the minimal finger movement and traces the best transitions.
Play with the metronome
Listen and play your chart at your own tempo (40-200 BPM), with metronome and loop mode.
Everything you need to connect chords well
A precise, calm and complete tool - without a single distraction.
The algorithm links each note of a chord to the closest note in the next one. The brass lines show the shortest path.
You pay once. No subscription, no hidden in-app purchases. While the whole market moves to monthly billing, HarmoniKeys stays yours, for good.
✓ No renewal, ever19 chord types
Major, minor, 7th, 6th, add, sus, diminished, augmented - the entire harmonic library.
Built-in metronome
40 to 200 BPM, loop mode, chart playback at your own tempo to drill your transitions.
100% offline
No account, no connection. The app works everywhere, in rehearsal and on stage.
Fingerings and inversions
Right or left hand, root position, 1st or 2nd inversion: the right fingering for each hand.
Ready-to-play charts
Canon, Blues, Jazz, Pop: load a progression in one tap. English notation (C-D-E) or solfège (Do-Re-Mi).
Discover the app
Keyboard and chords
19 chord types
Progression and voice leading
Chart library
The questions we get asked
Really no subscription?
Yes. HarmoniKeys is a single payment of 4.99 EUR. No monthly renewal, no hidden in-app purchases. Once you buy the app, it's yours - every feature included, forever.
Does it work offline?
Completely. No account to create, no connection required. Voice leading is computed on your device: the app stays fully functional in rehearsal, in lessons or on stage, even with no network.
Available on iPhone and Android?
Yes, HarmoniKeys is available on the App Store (iPhone, iPad) and on Google Play (Android). The same one-time purchase, the same features, on both platforms.
Your chords deserve to flow better
Optimal voice leading, in one tap. 4.99 EUR once, no subscription ever.
100% offline · No account · iPhone and Android.