Chord Finder

Find any chord fast. Choose a root note and chord type to see its notes and intervals, a playable guitar shape in standard tuning and the keys to press on piano. Or work backwards: type the notes you are playing and the finder names the chord, including inversions.

How chords are built

A chord is three or more notes played together, built by stacking intervals above a root note. A major chord takes the root, the major third (4 semitones up) and the perfect fifth (7 semitones up): A major is A–C♯–E. A minor chord lowers the third by a semitone: A minor is A–C–E. Seventh chords add a fourth note — a minor seventh (10 semitones) for dominant and minor 7ths, a major seventh (11 semitones) for maj7. Once you know the formulas, you can build any chord from any root.

Chord formulas

Reading the guitar diagram

• Vertical lines are strings, low E on the left to high E on the right.
• Horizontal lines are frets; a thick top line is the nut. A number such as “5fr” means the diagram starts at the 5th fret.
• Blue dots are fingered notes, labelled with their interval (R = root, 3 = third, and so on).
• ○ above a string means play it open; × means do not play it.
• The numbers under the diagram give the fret for each string from low to high, e.g. “x 0 2 2 1 0” for A minor.
• Press “Next guitar voicing” to see other shapes for the same chord up the neck.

Identifying a chord from notes

Type the notes you are playing, lowest first, such as E G C. The finder tests each note as a possible root against the chord formulas and names the first match. If the lowest note is not the root, it shows the chord as a slash chord — C/E means a C major chord with E in the bass, the first inversion. Spell notes with # or b (C# or Db); both names for the same pitch work.

Why the same chord has many shapes

On guitar, each note appears in several places on the neck, so every chord can be played in many positions. Open chords near the nut ring out with open strings and are easiest for beginners. Barre chords move one shape up and down the neck to play any root. Higher voicings with fewer strings suit rhythm parts in bands, where they leave room for bass and keys. The finder searches for shapes that span four frets or fewer, start from the root on the lowest played string and include all the essential notes.

Worked example

A songwriter wants a gentler sound than D major in a progression. They choose root D and type “add 9”: the notes are D–F♯–A–E. The finder’s first guitar shape is x 5 4 2 3 0, with the open high E string adding the 9th on top, and the piano diagram lights up D, F♯, A and E. Typing the notes back into “identify” as D F# A E returns Dadd9, confirming the spelling.

Chord theory tips

• In any major key, chords built on the scale degrees follow the pattern major, minor, minor, major, major, minor, diminished (I ii iii IV V vi vii°).
• The dominant 7th (V7) creates tension that resolves to the tonic (I).
• Sus chords sound open because they have no third; they often resolve to the major or minor chord.
• Power chords (root and fifth) are neither major nor minor, which is why they suit distorted guitar.
• Adding a 9th or 6th colours a chord without changing its basic function.

Common progressions to try

Use the finder to look up each chord’s notes and shapes, then try the progression in different keys by changing the root.

Privacy

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