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Music & Audio · Theory

Chord Finder

Pick a root note and a chord quality to see the exact notes — major, minor, seventh, and more, for guitar or piano.

Root noteThe note the chord is built on.
Chord qualityMajor, minor, seventh, and more.
C Major · C
C E G
C0 st
E4 st
G7 st
Interval formula
0 · 4 · 7
Notes
3

A chord is a set of notes stacked from a root. Add each interval in the chord’s formula (in semitones) to the root, wrapping every 12 semitones back into the octave. A C major chord uses 0-4-7, giving C E G; a Cmaj7 adds the 11th semitone for C E G B.

How chords are built

A chord is three or more notes sounded together, built by stacking thirds above a root. A third skips one letter name — C up to E, E up to G — and comes in two sizes: a major third (4 semitones) and a minor third (3 semitones). Which sizes you stack, and in what order, is what makes a chord major, minor, diminished, or augmented.

A three-note chord is a triad. A major triad stacks a major third then a minor third (4 + 3), so from C you get C, E, G. A minor triad flips the order (3 + 4), giving C, E♭, G. Add one more third on top and you reach a seventh chord — a four-note chord like Cmaj7 (C E G B) or the dominant C7 (C E G B♭) — the harmonic backbone of jazz, blues, and pop.

note = chromatic[(root + interval) mod 12]

Each chord note is the root’s position plus the interval in semitones, taken modulo 12 so it stays within the octave. C major = 0-4-7 counted up the chromatic scale from C.

Worked example

Spell an A minor chord. Minor is the formula 0-3-7, and A sits at position 9 in the chromatic scale (0 = C).

  1. 1
    Locate the root. Number the chromatic scale from C: C = 0, C♯ = 1, D = 2, up to B = 11. A is 9.
  2. 2
    Choose the chord formula. A minor triad is 0-3-7 semitones: root, minor third, perfect fifth.
  3. 3
    Add each interval to the root. 9 + 0 = 9, 9 + 3 = 12, 9 + 7 = 16.
  4. 4
    Wrap values back into the octave. Take each result modulo 12: 9, 12 mod 12 = 0, 16 mod 12 = 4.
  5. 5
    Read off the note names. Positions 9, 0, 4 are A, C, E — so A minor is A C E.

Chord qualities and their formulas

Interval formula in semitones from the root, with the notes each quality produces on a C root. Notes are spelled with sharps from the chromatic scale.

QualityFormula (semitones)Example on C
Major0-4-7C E G
Minor0-3-7C D♯ G
Diminished0-3-6C D♯ F♯
Augmented0-4-8C E G♯
Sus20-2-7C D G
Sus40-5-7C F G
Major 60-4-7-9C E G A
Minor 60-3-7-9C D♯ G A
Dominant 70-4-7-10C E G A♯
Major 70-4-7-11C E G B
Minor 70-3-7-10C D♯ G A♯
Minor 7♭5 (half-diminished)0-3-6-10C D♯ F♯ A♯
Diminished 70-3-6-9C D♯ F♯ A
Dominant 90-4-7-10-14C E G A♯ D
Add90-4-7-14C E G D

Reading the spellings

This tool spells every note with sharps from the chromatic scale, so a note may not match the letter name a musician would write. A C minor chord shows as C D♯ G, but the third is properly written E♭ — the same key on a piano, since D♯ and E♭ are enharmonic. Traditional notation names one note per letter (C, E♭, G), which is why the flat spelling looks tidier on a staff even though the pitch is identical.

The order shown is root position, the notes stacked from the root upward. Real players reorder or double notes to form inversions and voicings — a guitarist’s open C uses C E G spread across six strings — but the set of pitch classes stays the same. Start from the root-position spelling here, then rearrange to suit the instrument.

What notes are in a C major chord?
A C major chord is C, E, and G. It follows the major triad formula 0-4-7 semitones from the root: C is the root, E is the major third (4 semitones up), and G is the perfect fifth (7 semitones up).
What is the difference between a major and a minor chord?
The difference is the third. A major triad stacks a major third then a minor third (formula 0-4-7), while a minor triad uses a minor third then a major third (0-3-7). So C major is C E G, but C minor is C E♭ G — only the middle note moves down one semitone.
What is a seventh chord?
A seventh chord is a four-note chord that adds another third on top of a triad, reaching the interval a seventh above the root. A major 7 (0-4-7-11) gives Cmaj7 = C E G B, while a dominant 7 (0-4-7-10) gives C7 = C E G B♭. The added note gives the chord a richer, more colourful sound.
What is a sus chord?
A suspended chord replaces the third with a neighbouring note, so it sounds neither major nor minor. Sus2 uses the second instead of the third (0-2-7 → C D G) and sus4 uses the fourth (0-5-7 → C F G). They create an open, unresolved feel that often steps back to a plain major or minor chord.
What is a diminished chord?
A diminished triad stacks two minor thirds (0-3-6), so from C it is C E♭ G♭. A diminished seventh chord (0-3-6-9) adds another minor third for C E♭ G♭ B♭♭, dividing the octave into four equal parts. Both sound tense and are often used to lead into another chord.
Are these chords the same on guitar and piano?
Yes. A chord is defined by its set of notes, not the instrument, so C major is C E G whether played on guitar or piano. The instruments differ only in voicing — which notes are doubled or which octave they fall in — but the underlying notes this tool lists are the same.
Why does the tool show D♯ instead of E♭?
The tool spells every note with sharps drawn straight from the chromatic scale, so it shows C D♯ G for C minor. Musically the third is written E♭, but D♯ and E♭ are the same pitch (enharmonic equivalents) — the same key on a piano.