Hard soaps (), also termed soda soaps in older terminology, are categorized under soaps and are typically sodium salts of fatty acids. They vary in color from white to brownish and have a fatty acid content ranging from 72 to 75%. These soaps are typically made from lower-quality fats. Hard soaps serve as the foundation for products frequently labeled as fine soaps, which are fortified with nourishing additives, perfumes, and dyes.