This article presents hardenability curves for more than 80 types of carbon and alloy hardenability band (H-band) steels. Each H-band hardenability limit curve is presented graphically and in tabular form, in both metric and English units. The caption for each curve includes the normalizing and austenitizing heat-treating temperatures recommended by SAE for these steels. The article includes a brief description of how hardenability curves are used for specification purposes.