Keccak-256 & 4-Byte Selector Calculator

Calculate Ethereum Keccak-256 hashes, Solidity 4-byte function selectors, and EVM event topics.

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Common ERC Signatures:

Function / Event Signature:

4-Byte Function Selector (Method ID)

0xa9059cbb

First 4 bytes (8 hex characters) of Keccak-256 hash used in transaction calldata dispatch.

Full Keccak-256 Hash / Event Topic 0

0xa9059cbb2ab09eb219583f4a59a5d0623ade346d962bcd4e46b11da047c9049b