Chord Identifier

How to identify a chord with this tool

1. Enter your notes. On the Guitar fretboard tab, tap the fret you're holding on each string — tap a string's dot again to mute it, or hit "Mute all" to start clean. Prefer to think in note names? Switch to the Note names tab and tap the notes in your chord.
2. Read the name. The result updates the instant you change a note — no button to press. You get the chord symbol (like Cmaj7), its full name, the notes spelled correctly, and the interval formula (1 – 3 – 5 – 7).
3. Set the bass for slash chords. On the fretboard the lowest string you fret is the bass automatically, so an inversion shows as C/E. In note mode, tap a note in the "Lowest note" row to hear the same voicing named as a slash chord.
4. Check the alternates. The same notes can spell more than one chord — C6 and Am7 share all four notes. The tool names the most likely one and lists the rest under "Also called."
5. Hear it, copy it, print it. Tap Hear it to play the chord, copy the name and notes, share a link that reopens your exact voicing, or download a printable chord card with the fingering diagram.

Why this chord identifier is different

Most reverse chord finders online do the pitch math and stop — and several bury the answer under banner ads and app upsells. This one is built to actually teach you the chord:

• A real guitar fretboard, not just a note list. Tap the shape you're holding and the tool reads the voicing the way your hand plays it — including which string is the bass. If you're still learning shapes, our guitar chords for beginners guide has every open chord this tool will name.
• Musician-correct spelling. A C♯ major chord reads C♯ E♯ G♯, not "C♯ F G♯." The notes are spelled by their real letter names so the chord looks the way you'd write it on paper.
• It shows the formula, not just the name. Every result includes the interval degrees (1 – ♭3 – 5 – ♭7), so you learn why it's a minor 7th and can spot the pattern on the next chord.
• Honest about ambiguity. When notes could be two chords, it names the likely one and lists the alternates instead of pretending there's one right answer. The bass note breaks the tie.
• Free to hear, print, share and embed. Play the chord in your browser, save a chord card PDF with the diagram, share a link to the exact voicing, or embed the whole tool on your own teaching site.

How it works (the theory)

Every chord is a set of pitch classes measured in half-steps from a root. Name the twelve notes 0–11 (C = 0 up to B = 11), and a chord becomes a pattern of intervals that repeats no matter which note you start on:

major triad = root + 4 + 7      (1, 3, 5)      C E G
minor triad = root + 3 + 7      (1, b3, 5)     C Eb G
dom 7th     = root + 4 + 7 + 10 (1, 3, 5, b7)  C E G Bb

To identify a chord, the tool takes your notes, tries each one as a possible root, and measures the intervals up from it. When those intervals match a known formula — major, minor, diminished, sus, 6th, 7th, add9, ninth and so on — it has a name. If more than one root produces a match (C–E–G–A is both C6 and Am7), it ranks them by which note is in the bass and by how common each chord is, then lists the runners-up. When the lowest note isn't the root, the chord is written as a slash chord — same chord, new bass, like G/B. Two notes on their own are named as an interval, because a chord needs at least three.

Three chords worth identifying

The mystery shape you stumbled into

You slid an open chord up two frets, it sounds great, and you have no idea what it is. Tap the shape onto the fretboard and the tool tells you — often it's a sus, add9 or slash chord, the "colorful" voicings that make a progression sound less like a beginner's. Now you can write it down and use it on purpose.

Reading a chord out of a piano part

A songbook shows a cluster of notes with no chord symbol above it. Switch to the Note-names tab, tap the notes, set the bass, and you get the symbol to write over the staff — the same job MuseScore's chord tool does, but free and in your browser. If you're moving that chord to another instrument, our guide to reading guitar tabs shows how the same shape lands on a fretboard.

Checking your own voicing before you teach it

You're showing a student "that jazzy G chord" and want to be sure it's really a G13 and not a G9. Enter it, confirm the name and formula, and print the chord card. Pair it with a metronome and a tuner and the lesson runs itself — see our roundup of the best guitar tuners for keeping everything in pitch first.

Frequently asked questions

How do you identify a chord from its notes?

Pick one note as the root and measure the intervals up to the others in half-steps. Root, major third (4), perfect fifth (7) is a major chord; root, minor third (3), fifth (7) is minor; add a flat seventh (10) and it's a dominant 7th. This tool does that for all twelve possible roots at once and picks the name that fits — so you don't have to count frets by hand.

What chord has the notes C, E, G?

C–E–G is a C major chord — root C, major third E, perfect fifth G. Put a different note in the bass and it becomes a slash chord: C–E–G with E lowest is C/E, the first inversion. Enter it above to see the notes and formula laid out.

Why does one set of notes get two chord names?

Because chords are relative. C–E–G–A contains a C major triad plus an A, so it's a C6; but it also contains an A minor triad plus a G, making it Am7. Same four notes, two valid names — which one is "right" depends on the key and, above all, the bass note. That's why the tool lets you set the bass and shows the alternates.

Does the chord identifier work for piano too?

Yes. The note math is the same for any instrument — use the Note names tab, tap the keys you're playing, and set the lowest note as the bass. The Guitar fretboard tab is just a faster way to enter a voicing if you play guitar. If you play keys, our how-to-play guides translate the shapes both ways.

What's a slash chord, and how does the tool show it?

A slash chord is a chord played over a bass note that isn't its root — written chord/bass, like D/F♯ (a D major chord with F♯ in the bass). Whenever the lowest note you enter isn't the chord's root, the tool names it as a slash chord automatically, so inversions and pedal-tone voicings come out correctly instead of being mislabeled.

Related tools

• Chord Transposer — got the name? Move the whole progression to a new key with capo positions.
• Guitar Scales Chart — see which scale your chord belongs to, mapped across the fretboard.
• Guitar String Tension Calculator — dialing in a tuning for those voicings? Check your string tension.
• 120 BPM Metronome — lock the new chord into a progression at tempo.
• Browse all free musician's tools by Julian →

Gear to play the chords you find

Under your result the tool suggests specific gear based on what you found — a first electric and a spread of picks when you're on open chords, a capo and a good tuner once you're into 7ths and extended voicings. The logic is simple: a chord only sounds like the name says when the guitar is in tune and the strings ring, so a clip-on tuner and fresh picks matter more than people expect. If you're shopping the instrument itself, start with our guide to the best beginner electric guitars, then grab a set of the best guitar picks to find the gauge that makes your voicings cleanest.

Sources & methodology

• Identification model: pitch-class set matching — notes reduce to distinct pitch classes 0–11; for each candidate root the interval set (pc − root) mod 12 is matched exactly against a dictionary of chord formulas (all triads, sixths, sevenths, ninths, sus, add9, power and common shell voicings). Candidates are ranked by agreement with the bass note, then by chord commonness. Reference: musictheory.net chord-construction and interval lessons.
• Note spelling: chord tones are spelled by diatonic letter (the degree sets the letter, the accidental matches the pitch class), so thirds stack by letter the way written notation does.
• Fretboard: standard tuning E–A–D–G–B–E; the bass is the lowest fretted string.
• The engine is verified on every build by a fixture test covering every triad, the common sixths / sevenths / ninths / add and sus chords, slash-chord bass disambiguation, musician-correct spelling, and five open guitar-chord voicings.

Chord naming is contextual — the same notes can spell more than one chord depending on the key and the bass. This tool names the most common interpretation and lists the alternates. Reviewed by Julian Reyes, MM (Berklee). About Julian · Last reviewed August 3, 2026.

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