Piano Accordion Keyboards vary from 26 / 34 / 37 / 41 / 45, depending on manufacturer. They can be less than 26 or more than 45.

Piano Accordion Standard Bass Keyboards vary from 48 / 72 / 96 / 120, depending on manufacturer. They can be less than 48 or more than 120.

Button Accordion Keyboards come in various systems

  • “C” in the 3rd row.
  • “C” in the 1st row.
  • The button keyboard is also shown in catalogues as the number of buttons and actual number of notes eg. 105 / 64.

The Free Bass-Converter Bass Systems are also shown in catalogues as the number of buttons and actual number of notes eg. 120 / 58.