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What chord am I playing?

Identifying a chord by ear or by its notes is a skill every keyboard player needs. Here is how to figure out what chord you are playing — by interval, bass note, chord family, and live MIDI detection.

The core question

If you sit down at a keyboard and play a group of notes, how do you know what chord it is? Beginners often rely on memory — they learned that C–E–G is C major and stop there. But as soon as voicings get more complex, or you hear a chord on a recording and try to play it back, that memorization approach breaks down.

Understanding how to identify a chord from its notes — rather than just memorizing shapes — gives you the tools to figure out any chord you encounter.

Step 1 — Find the bass note

The bass note is the lowest note you are playing. It is the most important piece of information for chord identification because it tells you whether the chord is in root position or inverted.

If you are playing C–E–G and the lowest note is C, the chord is in root position. If the lowest note is E, you have a first inversion — and ChordBeam would show it as C/E. If the lowest note is G, it is second inversion — C/G.

The bass note gives the chord its starting point. Find it first, before thinking about anything else. In most voicings it is the leftmost key your left hand is playing.

Step 2 — Identify the pitch classes

Remove the octave. All Cs are the same note class, all Es are the same — it does not matter which octave they are in. Collect the unique note names from what you are playing.

Example — reducing to pitch classes
Playing: C3, G3, E4, Bb4
Pitch classes: C, E, G, Bb
Chord: C7 (dominant seventh)

Once you have the pitch classes, you can compare them against known chord formulas to find the match.

Step 3 — Match the interval pattern

Every chord type has a characteristic interval pattern above the root. If you know the intervals, you can identify the chord family even before you know the specific name.

Major triadRoot + maj 3rd + perf 5thbright, stable
Minor triadRoot + min 3rd + perf 5thdarker, softer
Dominant 7thRoot + maj 3rd + 5th + min 7thtense, bluesy
Major 7thRoot + maj 3rd + 5th + maj 7thlush, floating
Minor 7thRoot + min 3rd + 5th + min 7thsmooth, introspective
DiminishedRoot + min 3rd + dim 5thtense, unstable

Step 4 — Name it

Combine the root (from the bass note in root position) and the chord quality (from the interval pattern). C as the root with a major-triad pattern = C major. C as the root with a dominant seventh pattern = C7.

If the bass note is not the root — for example, the lowest note is E but the chord contains C, E, G — the chord is an inversion. It would be named C/E (C major, first inversion). The chord name comes from the pitch-class pattern, not from the bass note alone.

Common sources of confusion

The chord has 4 notes — is it still a triad?

Four-note chords are almost always seventh chords. The extra note is the seventh above the root. C–E–G–B is Cmaj7. C–E–G–Bb is C7. That one half-step difference changes the chord's function entirely.

The bass note does not match any chord I know

You might be playing an inversion. The bass note is not the root — the root is the note that makes the other notes fit a known pattern. Try identifying the pitch classes and matching them to a formula without treating the bass as root.

I can hear the chord but cannot name it

Play it into ChordBeam if you have a MIDI keyboard — the name appears instantly. Then use the displayed notes and chord type to reverse-engineer why it has that name. Hearing it while seeing the name is one of the fastest ways to build vocabulary.

Two chords sound similar but are labeled differently

Often this is the major vs. minor seventh difference. Cmaj7 and C7 are separated by one semitone on the top note. C minor and C major are separated by one semitone in the middle. Small changes in one note create different chord families.

How ChordBeam makes this instant

ChordBeam does the pitch-class analysis, interval matching and inversion detection automatically — in real time, while you play. Instead of working through the steps manually, you play a chord and see the result: chord name, note names, bass note and inversion, all at once. You can then read the name and confirm it against what you hear.

This is especially useful when you are trying to identify unfamiliar chords from a recording, figure out what your improvising hands just played, or check whether a chord you are writing is actually the quality you intended.

The Chord Library shows the same chords in a reference format, so you can study the formulas before or after using the live detector.

Identify your next chord in real time

Connect your MIDI keyboard and play any chord. ChordBeam shows you the name, notes, bass note and inversion immediately.

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