A kanna (カンナ) is a Japanese ceramic trimming tool crafted from a bent strip of steel—sometimes mounted on a wooden handle—used while the pot rests on the wheel to refine, trim, or texture vessels. Its open design yields multiple useful cutting edges, and its simplicity allows potters to customize shapes and maintain razor-sharp precision. Simple to make and easy to sharpen, the kanna combines versatility, efficiency, and the expressive control cherished in traditional pottery practices.