Identify

Chord Match Engine

Tap any set of notes and instantly identify the chord name, quality, and finger positions — across piano, guitar, and ukulele simultaneously.

Select Notes

Click notes on piano, guitar, or ukulele to build your chord

Tap notes to identify chords
Harmonic Analysis

19-Quality Formula Engine

Compares selected notes against 19 mathematical chord formulas, recognizing triads, 7ths, extended 9ths, and altered chords.

  • ✓Recognizes complex altered extensions
  • ✓Highlights passing notes vs chord tones
  • ✓100% client-side instant detection
Formulas
19 Chord Types
Calculation
< 1ms Engine
Inversions
Root / 1st / 2nd
Incomplete
Rootless Supported
Cross-Instrument

Multi-Instrument Voicings

Renders matching chord finger diagrams across Piano, Guitar fretboard, and Ukulele simultaneously for every result.

  • ✓Interactive finger position maps
  • ✓Fretboard shape visualization
  • ✓Easy transposition across instruments
Piano
Interactive Keybed
Guitar
6-String Diagrams
Ukulele
gCEA Fretboard
Layout
Side-by-Side
Collab Tool

Shareable URL Signatures

Every note combination generates a clean permalink URL so songwriters and teachers can share exact chord discoveries.

  • ✓Clean URL slug per note set
  • ✓Shareable via email or messaging
  • ✓Classroom & studio ready
URL Format
/chord-match/[notes]
Privacy
Zero Account Needed
State Sync
Instant Restore
Export
One-Tap Copy

How the Chord Match Engine Works

The Chord Match engine takes any set of notes you select and compares them against 19 chord quality formulas — from basic major and minor triads to extended 9th chords and half-diminished 7th chords. It runs entirely on the client-side — no server round-trips, no API calls — giving you instant identification.

When you select notes across multiple instruments (piano keyboard, guitar fretboard, ukulele), the engine union-sets your selections and identifies every possible chord those notes could form. Exact matches are highlighted first, followed by chord supersets (extra notes sitting on top of a known chord structure).

Chord Formula Detection

For each note set, the engine normalizes the pitch into semitone offsets from every possible root candidate. Then it compares the offset pattern against the chord formula intervals. In <1ms, it returns the root, the chord quality, the extra notes, and the matched confidence.

For musicians this means: you can explore the fingerboardhold mystery chords you stumble on, learn what they're called, and know exactly how to play them on piano, guitar, or ukulele — in one tab.

Chord Match — Frequently Asked Questions

Find answers to common questions about our virtual instruments, practice tools, and music theory workspace.

How does the Chord Match engine work?

Select any set of notes on the piano keyboard, guitar fretboard, or ukulele, and the engine compares them against every known chord formula (major, minor, 7ths, extended, and more).

It returns exact matches, shows voicings on all three instruments, and names the chord quality, root, and inversion.

Can it identify chords with passing notes?

Yes.

If you select more notes than the chord formula requires (e.g., adding a 9th to a major triad), the engine recognizes the core chord and lists the extra passing tones separately.

Does it show guitar finger positions?

Yes.

Every identified chord displays side-by-side finger diagrams for piano, guitar, and ukulele so you know exactly how to play it on any instrument.

What chord qualities are supported?

The engine identifies 19 chord qualities: major, minor, diminished, augmented, sus2, sus4, major 7th, minor 7th, dominant 7th, dim7, half-dim7, maj9, min9, dom9, add9, add11, 6th, minor 6th, and power chords.

Can I use this to learn new chords?

Yes.

Professional songwriters and beginners at both use the Chord Match to explore chord that sound similar, transpose them, and discover chord students naturally.

Does it work on mobile devices?

Yes.

The interactive piano, guitar, and ukulele all respond to touch input. Works on phones, tablets, and desktop browsers. No app download needed.

Can I share a specific chord match?

Every chord combination has a unique URL (e.

g., /chord-match/c-e-g) that you can bookmark or share via email, social media, or DM. The recipient sees the exact same chord voicings you found.