Ethereum Signatures API
Decode Ethereum smart-contract function and event signatures, keyless. Turn a 4-byte function selector (the first 4 bytes of any transaction calldata, e.g. 0xa9059cbb) into its human-readable function signature (transfer(address,uint256)), decode a 32-byte event topic from a log into its event signature, or search the database by name to find a selector. Many selectors have hash collisions — the API flags the original / canonical signature. Backed by the open 4byte.directory database, live. Essential for transaction decoders, block explorers, wallets, security tools and on-chain analytics — the signature-decoding layer for any EVM tooling.
api.oanor.com/ethsignatures-api
