πΉ Chord Calculator
Build chords or identify them from their notes.
Chord notes
How to Use This Calculator
Two tabs handle different directions. "Build a Chord" starts from a root note and chord type to show all the notes. "Identify from Notes" lets you click any combination of note names and the tool finds all matching chords. Both modes show the chord's intervals and inversions.
On "Build a Chord," select the root note (for example, G) and the chord type from the second dropdown (major, minor, dominant 7th, etc.). The notes appear instantly.
Read the note list and interval breakdown. Each note shows its role in the chord: root, 3rd, 5th, 7th. This tells you exactly which note in your voicing is which chord tone.
Check the inversions section. Each inversion places a different chord tone in the bass. First inversion puts the 3rd in the bass and gives the chord a lighter, less final sound.
On "Identify from Notes," click note buttons to select the notes you're hearing (order doesn't matter). The tool matches all standard chord types and shows every possible chord name that fits those notes.
Chord Construction Formula
R is the root note. Each interval is given in semitones above the root. A major 3rd is 4 semitones; a minor 3rd is 3 semitones. The difference between a major and minor triad is just that one semitone shift in the third: C major = C E G, C minor = C Eb G. Seventh chords add a fourth note. The dominant 7th (C E G Bb) is the most common in jazz, blues, and rock because the minor 7th creates tension that strongly pulls toward resolution.
Real-World Examples
When You Need This
If you hear a chord on a recording and want to figure out what it is, the identify tab is the fastest route. Play the chord slowly and pick out each note by ear or by hunting on a keyboard. Click those notes in the picker and the tool lists every chord that matches. A four-note cluster of C E G B comes back as C Major 7th. If you see two results (like C major and Am in first inversion share some notes), use the context of the song to decide which one applies.
Songwriters use the build tab when exploring chord progressions in unfamiliar keys. If you're writing in the key of Eb and want to use a secondary dominant before the IV chord, build an Ab dominant 7th here (Ab C Eb Gb) and confirm the notes before playing it. The inversions section also helps with voice leading: if C major to F major sounds clunky in your arrangement, switching F to first inversion (A in the bass) creates a smoother bass line and a more connected progression.
Frequently Asked Questions
What notes make a C major chord?
C major = C, E, G. It's built from root (C), major 3rd (E, +4 semitones), and perfect 5th (G, +7 semitones). This root-3rd-5th structure applies to all major chords.
What is a chord inversion?
A chord inversion places a note other than the root in the bass. C major root position: C-E-G. First inversion: E-G-C. Second inversion: G-C-E. The chord notes are the same; only the bass changes.
What is a dominant 7th chord?
A dominant 7th chord adds a minor 7th to a major triad: root + major 3rd + perfect 5th + minor 7th. Example: G7 = G, B, D, F. Common in jazz and blues, creates strong pull to the tonic.
What makes a chord diminished?
A diminished triad: root + minor 3rd + diminished 5th (= 3+3 semitones). Fully diminished 7th adds another minor 3rd (= 3+3+3 semitones). It has a tense, unstable sound.
What is the difference between a chord and an arpeggio?
A chord plays all notes simultaneously. An arpeggio plays the notes in sequence (broken chord). The notes are the same β only the timing differs.