A few polyfetts can form a square by joining variously sized copies of themselves. Here I show some examples.
The tilings shown use as few tiles as I know how, and are not necessarily unique under this condition. If you find a tiling with fewer tiles, please write.
Only polyfetts that are not polyaboloes are shown here. See also Similar Polyaboloes Tiling a Square.
Last revised 2021-01-28.