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FIPS 197

Advanced Encryption Standard (AES)

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.


National Institute of Standards and Technology



AES; block cipher; confidentiality; cryptography; encryption; Rijndael
Control Families

None selected


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)


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