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The Keyed-Hash Message Authentication Code (HMAC)

Published

Author(s)

National Institute of Standards and Technology (NIST), Quynh Dang

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. [Supersedes FIPS 198 (March 2002): http://www.nist.gov/manuscript-publication-search.cfm?pub_id=901425]
Citation
Federal Inf. Process. Stds. (NIST FIPS) - 198-1
Report Number
198-1

Keywords

computer security, cryptography, HMAC, MAC, message authentication, Federal Information Processing Standards (FIPS)

Citation

(NIST), N. and Dang, Q. (2008), The Keyed-Hash Message Authentication Code (HMAC), Federal Inf. Process. Stds. (NIST FIPS), National Institute of Standards and Technology, Gaithersburg, MD, [online], https://doi.org/10.6028/NIST.FIPS.198-1, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=901614 (Accessed October 6, 2025)

Issues

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Created July 16, 2008, Updated September 29, 2025
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