The Cm7b5 chord contains C, E♭, G♭ and B♭. Also written Cm7♭5 or Cø7, it combines a diminished triad with a minor seventh. Compare root position and three inversions.
Build the Cm7b5 chord from C–E♭–G♭ and add B♭, the minor seventh above C. Its formula is 1–♭3–♭5–♭7. Starting with Cm7, lower G to G♭ while retaining C, E♭ and B♭. The fifth changes, while the minor third and seventh stay in place.
Preserve the written chord spelling shown here; keyboard equivalence does not rename the chord.
Choose a position to keep the four written notes, sounding keys, bass note, playback and print reference synchronized.
Build the Cm7b5 chord with C, E♭, G♭ and B♭. G natural would give Cm7 instead. Choosing the A pitch class in place of B♭ would sound the diminished seventh B𝄫 above C. The exercise compares pitch classes, not a live piano performance.
Cm7♭5 uses 1–♭3–♭5–♭7: C–E♭–G♭–B♭.
a diminished triad plus a minor seventh
Compared with C diminished, add the minor seventh above the root.
A seventh chord has four chord tones and therefore four positions: root position plus three inversions. The slash symbol identifies the written bass note.
| Position | Symbol | Notes, low to high | Bass |
|---|---|---|---|
| Root position, current selection | Cm7♭5 | C4–E♭4–G♭4–B♭4 | C4 |
| First inversion | Cm7♭5/E♭ | E♭4–G♭4–B♭4–C5 | E♭4 |
| Second inversion | Cm7♭5/G♭ | G♭4–B♭4–C5–E♭5 | G♭4 |
| Third inversion | Cm7♭5/B♭ | B♭4–C5–E♭5–G♭5 | B♭4 |
The Cm7b5 chord diagrams identify written pitches and octaves without prescribing fingers. E♭ begins the first inversion, G♭ the second and B♭ the third. Keep the flat on G in each position; the bass label identifies the selected note order.
Use the written notes, keyboard positions and playback without treating the diagram as a required hand shape.
Read left- and right-hand finger numbersOpen Music Theory
Supports: Half-Diminished Seventh chord construction, written spelling and inversion principles
Scope: Supports theory and spelling only; keyboard layouts are PianoGrid examples, and no fingering is assigned.
C, E♭, G♭ and B♭: root, minor third, diminished fifth and minor seventh. The fifth is G♭ rather than G natural.
No. Both name the Cm7b5 chord. The flat-five symbol describes a minor seventh chord with a lowered fifth, while the slashed circle marks half-diminished quality.
The Cm7b5 chord uses B♭. Cdim7 uses B𝄫, which sounds on an A key on the piano. Checking the seventh distinguishes these two four-note collections.
E♭, G♭ and B♭ begin the first, second and third inversions. Root position begins on C. Selecting an option updates the written notes, bass, keyboard and reference sound.
Select the four pitch classes that make Cm7♭5, then check your answer.
This one-octave exercise checks the exact four-note pitch-class set. Order and inversion do not affect the result; missing and extra notes are reported, while fingering and live performance are not assessed.
One octave, C through B. Select a key again to remove it.
Chord tones: C–E♭–G♭–B♭ · Formula: 1, ♭3, ♭5, ♭7
Dots mark the notes to play. C4 is middle C. Numbers identify octaves, not fingers.