Chord Analyzer (online)

The combination of notes to form chords is huge, however, through inversions (change of bass) and transpositions all possible chords can be reduced to a few (exactly 19 chords of three notes, 43 of four notes, 66 of five notes and 80 of six notes) (see the complete list in Morphogenesis of chords and scales). If a structural equivalence is made between a chord and its (symmetric) inversion, then the chord classes are further reduced (this is what is known as Pitch Class Sets (introduced in 1973 by Allen Forte)). The numbers of PC-Sets of 3, 4, 5 and 6 notes are respectively 12, 29, 38 and 50. (both numerations appear in the chords shown)

On this page if we enter any chord (between 3 and 6 notes), the following 5 chords appear: the first is the chord as it has been entered, the second is a representative “harmonic” chord taking the tone C as a reference (‘fundamental’ position taking into account the harmonics/overtones of a sound), the third is a transposition of the second so that the notes match the original ones (with possible enharmonics), therefore it is the original chord in "harmonic" position, the fourth is the chord representing its (symmetric) inversion (also in “harmonic” position taking tone C as a reference) and the fifth is the (symmetric) inversion of the chord entered.
Below, the main fundamentals of the chord appear (see 3.1 in Functional study of chords). Briefly, a note (fundamental) in capital letters indicates that it has its major third, in lowercase letters mean it doesn't have its major third, a striked-out note (e.g. C) refers to being a virtual fundamental (see 2.2 in The harmonics of a sound as the basis of musical perception and https://www.youtube.com/watch?v=0Y4-NQQ6hAY) (a 7 indicates that the fundamental has its minor seventh). From these main fundamentals the representative "harmonic" chord is constructed. The name of the chord (and other properties) also appears if it is known and, for chords of 3 and 4 notes, we also show the symbols that are usually used in popular music / jazz, although this symbology is not currently standardized. This notation depends a lot on the bass of the chord, for this reason we have not calculate it in chords with more than 4 notes because the notation possibilities grow enormously depending on the bass of the chord.

The chord is entered with the letters that define the notes (in capital letters) and their accidentals (in lowercase letters: #, b) without intermediate spaces. Do not repeat notes (even enharmonic) nor use bb (double flat). Examples: EbCG#Bb refers to the chord: E flat - C natural - G sharp - B flat (Mi b - Do - Sol # - Si b). C#CBBb to the chord: C sharp - C natural - B natural - B flat. (Use Ctr+scroll wheel to adjust chord comments position)

Enter chord (e.g.: EbCG#Bb): (if you cannot enter or change the chord use Ctr+/Ctr- or Ctr+scroll wheel to adjust chord comments and/or reload page)
(from 3 to 6 notes)
(for those interested there is a plugin for sibelus (free) with similar analyzes)