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 197 Advanced Encryption Standard (AES) Share to Facebook Share to X Share to LinkedIn Share ia Email Documentation Topics Date Published: November 26, 2001; Updated May 9, 2023 Supersedes: FIPS 197 (11/26/2001) Planning Note ( 05/09/2023 ): This release updates the original publication of FIPS 197 (2001), but makes no technical changes to the algorithm specified in the standard. However, this update includes extensive editorial improvements, including the following: The front matter is modernized (e.g., a foreword and abstract are added). Terms and symbols are defined more comprehensively and consistently. Formatting/typesetting is improved in a variety of ways. Unnecessary formalism is removed. Diagrams for the three key schedules are included. Some references were updated, and additional references are provided. See the announcement of this update for more details about the FIPS 197 review process. Author(s) National Institute of Standards and Technology Abstract In 2000, NIST announced the selection of the Rijndael block cipher family as the winner of the Advanced Encryption Standard (AES) competition. Block ciphers are the foundation for many cryptographic services, especially those that provide assurance of the confidentiality of data. Three members of the Rijndael family are specified in this Standard: AES-128, AES-192, and AES-256. Each of them transforms data in blocks of 128 bits, and the numerical suffix indicates the bit length of the associated cryptographic keys. In 2000, NIST announced the selection of the Rijndael block cipher family as the winner of the Advanced Encryption Standard (AES) competition. Block ciphers are the foundation for many cryptographic services, especially those that provide assurance of the confidentiality of data. Three members of... See full abstract In 2000, NIST announced the selection of the Rijndael block cipher family as the winner of the Advanced Encryption Standard (AES) competition. Block ciphers are the foundation for many cryptographic services, especially those that provide assurance of the confidentiality of data. Three members of the Rijndael family are specified in this Standard: AES-128, AES-192, and AES-256. Each of them transforms data in blocks of 128 bits, and the numerical suffix indicates the bit length of the associated cryptographic keys. Hide full abstract Keywords AES ; block cipher ; confidentiality ; cryptography ; encryption ; Rijndael Control Families None selected Documentation Publication: https://doi.org/10.6028/NIST.FIPS.197-upd1 Download URL Supplemental Material: None available Related NIST Publications: IR 8319 Document History: 12/19/22: FIPS 197 (Draft) 05/09/23: FIPS 197 (Final) Topics Security and Privacy encryption 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