C–E–G: C major
Select the white keys C, E and G. They form a major triad because E is four semitones above C and G is seven semitones above C. The same three pitch classes can appear as E–G–C or G–C–E when the chord is inverted.
Free interactive toolChord finder
Chord finder
by piano notes.
Know the notes but not the chord name? Choose three or four pitch classes. We'll match all ten chord families in the 120-chord library and show alternative names when the same piano keys admit different interpretations.
Select your notes
Choose a set of 3 or 4 distinct pitch classes. Octaves don't change the basic chord identification.
Choose the physically lowest note if known. A chord tone gives its inversion (for example C/E); a different bass note produces a slash-chord interpretation, not an inversion.
Chord names can be ambiguous without a bass note, key and harmonic context.
How the chord finder works
The finder compares selected pitch classes against ten formulas: major, minor, diminished, augmented, suspended second, suspended fourth, dominant seventh, major seventh, minor seventh and half-diminished seventh. It uses twelve-tone equal temperament and matches pitch classes, not the musical key. The optional bass selector lets you name an inversion such as C/E when E is the lowest note; a non-chord bass is marked as a separate slash-bass interpretation rather than a false inversion. Several names can still be valid. Continue to the 120-chord inversion explorer to hear the actual voicings.
LEARN BY EXAMPLE
Identify piano chords from the notes you have
Start with three notes, check the results, and use the sound and bass note to choose the right interpretation.
A–C–E: A minor
Choose A, C and E. The interval from A to C is a minor third (three semitones), which distinguishes A minor from A major (A–C♯–E). A minor and C major share two notes, but they are different chords.
C–E–G–B♭: C7
Adding B♭ to C major makes a dominant seventh chord, C7. If the top note is B natural instead, the chord is Cmaj7. That one-semitone difference changes the seventh quality.
Why can a chord have more than one name?
This finder matches pitch classes: C4 and C5 both count as C. It uses the bass you specify, but does not hear the physical octave or decide which chord function a composer intended. Some note sets can legitimately match several chord names or enharmonic spellings. Do not assume that the first match is the only correct one.
If you know which note is lowest, visit the inversion explorer to identify the chord's bass and compare its voicings. To hear how a chord changes into another, use the side-by-side comparison tool.
What if your chord is not recognised?
The tool currently supports ten families of three- and four-note chords. A five-note extended chord, a chord missing its root, or a note cluster outside those formulas may not return a match. That is a scope limit of this tool, not proof that the notes cannot be musical.
Try entering only the chord tones you know, or use the 88-key virtual piano to hear the complete voicing. You can also browse the 29 authored lessons for worked note spellings.