Skip to content

Ethereum Toolset

Tokens Collections Mint NFT Contracts Holders Faucets Learn Guides

Tool · Hashing

Function Selector

Compute the 4-byte function selector for any signature.

Home
Tools
Function Selector

Function selector

Function signature

4-byte selector

0xa9059cbb

About this tool

Selector = first 4 bytes of keccak256 of the canonical signature. Useful when reading raw calldata or verifying custom errors.

All computation happens locally in your browser. No inputs are sent to a server.

Related

Keccak-256 Hash

Compute Keccak-256 of any UTF-8 or hex input.

SHA-256 digest for content verification.

Ethereum Toolset

Deploy audited OpenZeppelin contracts, mint NFTs, and access professional Ethereum developer tools — no coding required.

Built by Ibrahim Wali

Deploy

Token Creator
NFT Collection
Mint NFT Asset
Contract Wizard
Contract Manager

Tools

Developer Tools
Holders Snapshot
Testnet Faucets
ABI Encoder
Keccak Hash

Resources

Learn Ethereum
Guides
OZ Skills
Dashboard
Donate
Developer

© 2026 Ethereum Toolset. All contracts are based on OpenZeppelin. Not financial advice.

Developer Sitemap Robots