Abstract: The revision of two international standards of Knoop hardness test method ISO 4545-1:2023 and Vickers hardness test method ISO 6507-1:2023 was proposed and finally published. The main work of this revision was to add a normative appendix to each of these two international standards to provide technical specifications for hardness tests of metal and other inorganic coatings and replace the original ISO 4516:2002. The revision work provided a successful case for the merger of international standards and integrated similar standards.The standard reduced the number of standards, optimized the content of standards, and improved the quality of standards.