You are viewing this page in an unauthorized frame window. This is a potential security issue, you are being redirected to https://csrc.nist.gov . An official website of the United States government Here’s how you know Here’s how you know Official websites use .gov A .gov website belongs to an official government organization in the United States. Secure .gov websites use HTTPS A lock ( Lock Locked padlock icon ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites. Search Search CSRC MENU Search Search Projects Publications Expand or Collapse Drafts for Public Comment All Public Drafts Final Pubs FIPS (standards) Special Publications (SP s ) IR (interagency/internal reports) CSWP (cybersecurity white papers) ITL Bulletins Project Descriptions Journal Articles Conference Papers Books Topics Expand or Collapse Security & Privacy Applications Technologies Sectors Laws & Regulations Activities & Products News & Updates Events Glossary About CSRC Expand or Collapse Computer Security Division Cryptographic Technology Software Security Group Hardware Security Group Security Engineering and Risk Management Applied Cybersecurity Division Cybersecurity and Privacy Applications National Cybersecurity Center of Excellence (NCCoE) National Initiative for Cybersecurity Education (NICE) Contact Us Information Technology Laboratory Computer Security Resource Center Publications FIPS 198-1 The Keyed-Hash Message Authentication Code (HMAC) Share to Facebook Share to X Share to LinkedIn Share ia Email Documentation Topics Date Published: July 2008 Supersedes: FIPS 198 (03/06/2002) Planning Note ( 06/23/2025 ): A Federal Register Notice solicits feedback by July 23, 2025 , on NIST's plans to withdraw this FIPS and moving its content to a new NIST Special Publication, SP 800-224 . You can monitor developments by subscribing to our GovDelivery notices and selecting the "FIPS" and "Draft Publications" topics. Author(s) National Institute of Standards and Technology Abstract This Standard describes a keyed-hash message authentication code (HMAC), a mechanism for message authentication using cryptographic hash functions. HMAC can be used with any iterative Approved cryptographic hash function, in combination with a shared secret key. This Standard describes a keyed-hash message authentication code (HMAC), a mechanism for message authentication using cryptographic hash functions. HMAC can be used with any iterative Approved cryptographic hash function, in combination with a shared secret key. Keywords MAC ; message authentication ; Federal Information Processing Standards (FIPS) ; computer security ; HMAC ; cryptography Control Families Audit and Accountability ; System and Communications Protection ; System and Information Integrity Documentation Publication: https://doi.org/10.6028/NIST.FIPS.198-1 Download URL Supplemental Material: Submit comments on proposed withdrawal by 7/23/25 Document History: 07/16/08: FIPS 198-1 (Final) Topics Security and Privacy message authentication Laws and Regulations Federal Information Security Modernization Act HEADQUARTERS 100 Bureau Drive Gaithersburg, MD 20899 X (link is external) facebook (link is external) linkedin (link is external) instagram (link is external) youtube (link is external) rss govdelivery (link is external) Want updates about CSRC and our publications? Subscribe Contact Us | Our Other Offices Send inquiries to [email protected] Site Privacy Accessibility Privacy Program Copyrights Vulnerability Disclosure No Fear Act Policy FOIA Environmental Policy Scientific Integrity Information Quality Standards Commerce.gov Science.gov USA.gov Vote.gov