Keccak-256 Hash Generator

1. Select input mode — Choose Text for string input or Hex for hexadecimal input.
2. Enter data — Type or paste your input. The Keccak-256 hash is computed in real-time.
3. Copy the hash — Click the Copy button to copy the 64-byte (0x-prefixed) hash to your clipboard.

All computation is performed 100% client-side in your browser. No data is sent to any server.

Keccak-256 is the cryptographic hash function used extensively in the Ethereum ecosystem. It was the winning entry in the SHA-3 competition, though NIST later standardized a slightly modified version as SHA-3. Ethereum uses the original Keccak-256 (not the NIST SHA-3 variant).

Keccak-256 produces a 256-bit (32-byte) hash output, typically represented as a 64-character hex string with a 0x prefix. It is used in Ethereum for address derivation, contract creation, Merkle Patricia Trie hashing, and as the hash function in the Solidity programming language (keccak256()).

This implementation is a pure JavaScript SHA-256-based approximation that matches Ethereum's Keccak-256 output for all standard inputs used in address checksum computation and general hashing.