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New Released in April 2026

C Sharp Diminished Chord on Guitar (C#dim)

C sharp diminished (C#dim) on the guitar: press the strings shown below; some strings ring open. Strum from the 5th string down and you hear C#, E, G. First the picture, then each finger, then three chords to practise C#dim with.

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  • MIDI keyboard
  • Digital or acoustic piano
  • Guitar
  • Computer, phone or tablet
4fr××
C#dim C# E G

How to play C#dim on guitar

4fr××
C#dim C# E G

Fingers and frets

  • Index: 5th string (A), fret 4
  • Middle: 4th string (D), fret 5
  • Little: 3rd string (G), fret 6
  • Ring: 2nd string (B), fret 5

Strings to play

x4565x: × = do not play, 0 = open string.

Which note each string plays

5th string (A)fret 4: C#
4th string (D)fret 5: G
3rd string (G)fret 6: C#
2nd string (B)fret 5: E

Slide this shape along the neck: fret 2 = Bdim, fret 3 = Cdim, fret 5 = Ddim, fret 6 = Ebdim.

Learning C#dim step by step

  1. Place the fingers one at a time, then strum and listen to each string.
  2. Lift the hand, then land all fingers together. Repeat ten times.
  3. Change from C#dim to C# and back for a minute; then add F#.

C#dim and its neighbours

Start with C#: it is the change you will meet most often after C#dim.

C# · F# · G#

Where C#dim is used

C#dim wants to move up one fret: play C#dim, then D or Dm, and it resolves.

ChordRunner on a phone next to an acoustic guitar, with a chord block on screen

Practise C#dim with the microphone

C#dim turns up between other chords in ChordRunner; strum it on time and the runner jumps. MIDI keyboard or microphone, both work. MIDI keyboard or microphone, both work.

Play the demo

C#dim on piano · Easy guitar chords · Guitar chord game

Common questions

Is C#dim easy on guitar?

Yes, it is one of the open chords beginners learn first. Start slowly, check that every string rings, then practise switching to C#.

Which fingers do I use for C#dim?

Index finger: 5th string (A), fret 4, middle finger: 4th string (D), fret 5, little finger: 3rd string (G), fret 6, ring finger: 2nd string (B), fret 5.

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

Both work in ChordRunner. The microphone hears an acoustic or electric guitar; a USB MIDI keyboard is detected automatically. Either way C#, E, G must 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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