All tools

• web3

  ABI Decoder & Encoder

  Decode calldata and event logs, or encode function calls, using any contract ABI.

• web3

  Ethereum / EVM Unit Converter

  Convert between Wei, Gwei, and Ether, and estimate gas fees for legacy or EIP-1559 transactions.

• web3

  Smart Account (ERC-4337) UserOp Builder

  Build an ERC-4337 UserOperation for EntryPoint v0.6 or v0.7 and see its JSON, packed encoding, and UserOpHash.