Keyboard Widget

This keyboard highlights the currently playing Chord, bass and Vertical Scale. Open additional panels with Window > Keyboard at any size.

Show Vertical Scale instead of Chord.
All Octaves
Extend scale highlighting to all octaves.
MIDI Input
Display live MIDI input. If you want a palette to respond to keys presses here, also check MIDI Input with the palette.
Mouse Wheel
Scroll octave range.
⌘Click Control-Click
Set or unset keyboard split for live input.
Tip: For playing along on a piano or synthesizer, you can change the size to make fingerings easily readable from a distance.