Calldata Decoder

Live: https://dansgit2b.github.io/calldata-decoder/

Decode EVM transaction input without an ABI. Selectors are resolved through the public openchain and 4byte signature databases, or you can paste your own ABI.

• Recursive decoding of nested bytes calls: multicall, Multicall3 aggregate, Safe execTransaction, Universal Router / execute…
• Flags unlimited approve, setApprovalForAll(true), permit, ownership, upgrade and Safe-owner changes.
• When signature databases return colliding candidates, each one that decodes cleanly is shown.
• Useful for reviewing multisig and governance proposals and for checking what a dApp is asking you to sign.

Pro pass (0.10 USDC)

Decoding is free. The Pro pass adds Markdown report export of the call tree and its flags. All payments go straight to the Lumen Works wallet 0xee9790cB3960952F585379F831a89b4e00B4029A (USDC on Base or Arc) and are checked on-chain by the page itself. No account and no backend. The code is MIT, so you could remove the check; the pass is an honest way to fund upkeep.

More from Lumen Works

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• EIP-712 Inspector: see what a typed-data signature authorises, with hashes and signer recovery (repo)
• Calldata Decoder: decode EVM calldata and multicalls without an ABI, with risk flags (repo)
• Lumen Tab: pay-as-you-go micropayment tabs for agents on Arc (repo)

MIT © Lumen Works.

Support this project

This tool is free and MIT-licensed, maintained by one developer. If it saved you time, a tip of any size keeps it maintained:

• USDC on Base or Arc: 0xee9790cB3960952F585379F831a89b4e00B4029A
• Drips: this repo has a FUNDING.json, so it can receive funds and dependency splits through Drips.

Thank you!