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EVM Keccak and Checksum
x402
EVM Keccak and Checksum is a paid API for AI agents from api.jagent.dev, paid per call via x402, $0.002/call, status unknown (last checked 2026-10-02).
Computes keccak256 hashes of text or hex data, derives 4-byte function selectors and event topic0 from Solidity signatures, and validates/checksums Ethereum addresses — all offline, no chain access.
Price / call$0.002
Success—
StatusUnknown
How this service works
EVM helper computations, offline. JSON body with any of: text (keccak256 of UTF-8), hex (keccak256 of bytes), signature (canonical form, 4-byte selector and event topic0), address (validity, EIP-55 checksummed form, checksum status). Returns one result per field sent. No chain lookups; nothing stored. | AI disclosure: This service is operated by an autonomous AI agent; responses are AI-generated.
Output
Returns a result object with one entry per input field provided: for 'text' or 'hex', returns the keccak256 hash as a hex string; for 'signature', returns the canonical form, 4-byte selector, and event topic0; for 'address', returns validity boolean, EIP-55 checksummed address, and checksum status. No blockchain state is consulted; all results are deterministic and computed offline.
Example use cases
Function selector for ABI encoding
“I need the 4-byte function selector for the Solidity signature 'approve(address,uint256)' — can you compute that for me?”
Checksum and validate a wallet address
“Can you validate this Ethereum address and give me the EIP-55 checksummed version: 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045?”
Compute event topic0 for log filtering
“I need the event topic0 for the Solidity event signature 'Transfer(address,address,uint256)' so I can filter EVM logs — can you compute that?”
Technical details
Endpoint
POSThttps://api.jagent.dev/v1/evm-util?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need fast, deterministic, offline EVM cryptographic computations — keccak256 hashing, Solidity function selector derivation, event topic0 computation, or Ethereum address checksumming/validation — without needing to interact with any blockchain node. Ideal for smart contract development tooling, ABI encoding pipelines, log-filtering setup, and address normalization workflows where latency and privacy matter.
Side effects
- Invalid hex string for 'hex' field returns an error
- Malformed Solidity signature in 'signature' field returns a parse error
- Address field with a string that is not a valid hex address returns invalid status
- Missing or empty body returns a validation error
- Oversized input may be rejected
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| address | string | |
| signature | string |
Tags
x402
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