Interactive piano keyboard showing C# Lydian scale degrees. Click highlighted keys to play.
C♯ lydian has a raised 4th that creates its signature floating, dreamy quality. Its key signature is enharmonically equivalent to four flats (the A♭ major system), and the augmented 4th (G natural) produces the ethereal, unresolved character central to the lydian sound. It is used in jazz and progressive rock over C♯maj7 chords.
The raised 4th is Lydian’s only difference from major, but it transforms the sound completely — creating a dreamy, floating quality where nothing feels like it needs to resolve. The augmented 4th gives an ethereal brightness unlike any other mode.
The seven diatonic modes — parallel modes starting from the same root with different interval patterns. Each mode has a unique character derived from the major scale.
The diatonic chords in C# Lydian are: C#, D#, Fm, Gdim, G#, A#m, Cm. These are the chords built naturally from each degree of the scale.
What is the Lydian?
C♯ lydian has a raised 4th that creates its signature floating, dreamy quality. Its key signature is enharmonically equivalent to four flats (the A♭ major system), and the augmented 4th (G natural) produces the ethereal, unresolved character central to the lydian sound. It is used in jazz and progressive rock over C♯maj7 chords.
What notes are in the C# Lydian?
The C# Lydian contains the notes: C#, D#, E#, F##, G#, A#, B#. This is a 7-note scale starting from C#.
How many chords does the C# Lydian have?
The C# Lydian produces 7 diatonic chords, one built on each degree of the scale: C#, D#, Fm, Gdim, G#, A#m, Cm.
What is the formula for the Lydian?
The Lydian follows the interval formula: W-W-W-H-W-W-H (W = whole step, H = half step).
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Position in circle of fifths
C# is at the 7 o'clock position. Related keys: Ab (dominant), F# (subdominant), Bb (relative minor), Eb (supertonic), B (subtonic).