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New Released in April 2026

F Sharp Diminished Chord on Piano (F#dim)

To play F#dim on the piano, press F#, A, C together. Start from F#m and move the fifth down a semitone: that one key turns it into F#dim. Below: the keyboard, the three positions, how it compares with F# and F#m, and where it goes next.

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  • MIDI keyboard
  • Digital or acoustic piano
  • Guitar
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F#dim F# A C

How to play F#dim on the piano

Any order of F#, A, C is still F#dim.

F#dim F# A C

Root position: F# A C

F#dim A C F#

1st inversion: A C F#

F#dim C F# A

2nd inversion: C F# A

  • Root position: starts on F#, a black key; black keys: F#
  • 1st inversion: starts on A, a white key; black keys: F#
  • 2nd inversion: starts on C, a white key; black keys: F#

What makes F#dim different

Same root, same third or fifth moved by a semitone.

ChordNotesThirdFifth
F# F# A# C#major 3rdperfect 5th
F#m F# A C#minor 3rdperfect 5th
F#dim F# A Cminor 3rddiminished 5th
F#aug F# A# C##major 3rdaugmented 5th

F#dim in keys and progressions

  • F#dim is the vii° chord of G major and the ii° chord of E minor.
  • It wants to move up a semitone: F#dim → G / Gm, the bottom note rising to the new root.
  • Add E and you get F#m7b5 (half-diminished); add Eb instead and you get F#dim7 (diminished 7th).

F#m7b5 · G

ChordRunner showing a chord block while hands play the piano

Make F#dim automatic

ChordRunner mixes F#dim with the chords around it and checks every note you play. MIDI keyboard or microphone, both work.

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All piano chords · Diminished chords explained

Common questions

How do you play F#dim on the piano?

Press F#, A, C together: right hand 1-3-5 with the thumb on F#, left hand 5-3-1 with the little finger on F#.

What is the difference between F#dim and F#m?

One note. F#m has C# on top; F#dim moves it to C. The new fifth is what gives F#dim its tense sound.

Where does F#dim go?

F#dim is the vii° chord of G major and the ii° chord of E minor. It wants to move up a semitone: F#dim → G / Gm, the bottom note rising to the new root.

Can I practise F#dim with a MIDI keyboard or microphone?

Yes. ChordRunner detects a USB MIDI keyboard automatically and also hears an acoustic piano through the microphone. F#dim counts in any position, as long as F#, A, C sound together.

Your instrument is the controller.

ChordRunner is a browser game that teaches piano and guitar chords: a chord appears on screen, you play it on a real instrument, and your runner jumps. MIDI keyboard or microphone, both work.

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