Sharpening stones, water stones or whetstones are used to sharpen the edges of steel tools and implements through grinding and honing.

Examples of items that can be sharpened with a sharpening stone include scissors, scythes, knives, razors, and tools such as chisels, hand scrapers, and plane blades.

Sharpening stones come in a wide range of shapes, sizes, and material compositions. Stones may be flat, for working flat edges, or shaped for more complex edges, such as those associated with some wood carving or woodturning tools. They may be composed of natural quarried material, or from man-made material.