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Keccak-256 Hash

Hash text or raw hex bytes with Keccak-256, the hash function used across the EVM for storage slots, event topics and signatures. Paste a function signature like transfer(address,uint256) and the 4-byte selector is shown too.

Private by default: processing stays on your device
Input is:

Example: ERC-20 transfer selector

Input

transfer(address,uint256)

Output

Selector: 0xa9059cbb
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Frequently asked questions

Is Keccak-256 the same as SHA3-256?

No. Ethereum adopted Keccak before NIST finalized SHA-3 with different padding, so the two produce different digests for the same input. Solidity's keccak256() and this tool use the original Keccak padding.

What is a function selector?

The first 4 bytes of the Keccak-256 hash of a function's canonical signature, e.g. transfer(address,uint256) → 0xa9059cbb. The EVM uses it as the first 4 bytes of calldata to route a call to the right function.

What does the hex input mode do?

Text mode hashes the UTF-8 bytes of what you type. Hex mode treats the input as raw bytes (0x-prefix optional), which is what you need to reproduce hashes of ABI-encoded data or addresses.

Is my input uploaded anywhere?

No. Hashing runs entirely in your browser via a small JavaScript implementation, safe for secrets and unreleased contract code.

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Hash Generator

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