Chord · F# Half-Diminished 7th (m7♭5)
F♯m7♭5 Chord
F♯m7♭5 is F#, A, C and E — the ii in a minor ii-V-i.
F♯m7♭5 on every instrument
The same 4 notes, 6 sets of hands. Open a diagram for alternate shapes, audio and the mistakes to avoid.
What F♯m7♭5 is made of
F# Half-Diminished 7th (m7♭5) (F# half-diminished 7th (m7♭5)) is built from the notes F#, A, C, E, with the interval pattern 1, b3, b5, b7. A common half-diminished 7th (m7♭5) chord across many styles.
Stack 1, b3, b5 and b7 on a root of F♯ and you get F#, A, C and E. That interval recipe is what makes the chord a half diminished seventh chord — move the same shape to another root and the character travels with it, which is why Cm7♭5 sounds like a transposed F♯m7♭5.
Half-Diminished 7th (m7♭5): The ii in a minor ii-V-i.
Spelling: the notes above are written the way a score would write them, not simplified to the nearest piano key. That is why this chord is spelled with F♯ rather than its enharmonic equivalent.
Keys that contain F♯m7♭5
All 4 notes sit inside the scale of 2 keys. The roman numeral marks the degree the chord is rooted on.
Major keys
Minor keys
Other chords on F♯
Same root, different colour.
The same half diminished seventh shape, moved
The identical interval recipe, built on other roots.
Questions people ask about F#m7b5
- What notes are in the F#m7b5 chord?
- F#m7b5 is made of F#, A, C and E — the 1, b3, b5 and b7 degrees of a half diminished seventh chord built on F#.
- What keys use the F#m7b5 chord?
- Every note of F#m7b5 belongs to 2 keys: G Major (vii°), E Minor (ii°). The roman numeral is the scale degree the chord is rooted on.
- How do you play F#m7b5 on guitar and piano?
- This page shows F#m7b5 on guitar, piano, ukulele, bass, mandolin and banjo — 9 voicings in total. Each diagram links to the full instrument page with alternate shapes, audio and common mistakes.
- Is F#m7b5 the same as Gbm7b5?
- Yes. F#m7b5 and Gbm7b5 are enharmonic — identical pitches written two different ways. Which spelling you use depends on the key you are in; F#m7b5 is the spelling this site treats as canonical.
Learn the theory behind it
Why F♯m7♭5 behaves the way it does — the guides that explain the chord instead of just spelling it.