Keccak hash calculator

Calculate Keccak hashes for text or files to check data integrity.

Output length

256

Input

Paste or type any UTF-8 text, including emoji and non-Latin characters.

Checksum

Checksum for the current text input.

Hexadecimal

Base64

Decimal

Binary

What is Keccak?

Keccak is a family of cryptographic hash functions that serves as the foundation for the SHA-3 (Secure Hash Algorithm 3) standard. Developed by Guido Bertoni, Joan Daemen, Michaël Peeters, and Gilles Van Assche, it won the NIST hash function competition in 2012.

Key characteristics:

  • Sponge construction: Uses an innovative sponge function design with absorbing and squeezing phases
  • Variable output length: Can produce hash outputs of any desired length
  • High security margin: Designed with substantial security reserves
  • Different from SHA-1/SHA-2: Based on entirely different mathematical principles
  • Keccak[c=2d] variant: This implementation uses the original Keccak specification with capacity c = 2d (where d is the output length)

Keccak vs SHA-3 (FIPS 202) differences:
Original Keccak and standardized SHA-3 are not identical:

  • Original Keccak: Uses capacity c = 2d and different padding (Keccak padding: 0x01)
  • FIPS 202 SHA-3: Uses capacity c = 2d but different padding (SHA-3 padding: 0x06)
  • Domain separation: The padding difference ensures that Keccak and SHA-3 produce different outputs for the same input
  • This tool implements: The original Keccak specification with Keccak[c=2d] parameterization

Security status:
✅ Keccak is considered highly secure with no known practical attacks. It provides excellent security margins and resistance against various cryptanalytic techniques.

Common uses:

  • Ethereum blockchain (uses original Keccak-256)
  • Academic research and cryptographic protocols
  • Applications requiring variable-length hash outputs
  • Systems needing alternatives to SHA-2 family
  • Blockchain and cryptocurrency implementations

Advantages over traditional hashes:

  • Fundamentally different design reduces risk of related attacks
  • Flexible output length (not limited to fixed sizes)
  • Strong theoretical security foundation
  • Resistance to length extension attacks
  • Excellent performance on various platforms

Technical note:

  • Keccak-256: Produces 256-bit output (most common variant)
  • Capacity formula: c = 2d ensures appropriate security level
  • Ethereum usage: Ethereum specifically uses original Keccak-256, not SHA3-256

How to use

Choose text or a raw file, select output bits and calculate. Switch result formats or copy. Confirm that your protocol needs Keccak rather than SHA-3