Look up an EIP/ERC by number API

Resolves an EIP or ERC number to structured metadata — title, status, type/category, author, requires-graph, discussions link, and a trimmed abstract — across both canonical repos (ethereum/EIPs and ethereum/ERCs). Answers 'what is EIP-1559?', 'is ERC-4626 final?', 'what does this EIP require?'.

Price$0.01per request

MethodPOST

Route/v1/chain/eip-lookup

StatusLive

MIME typeapplication/json

Rate limit60/minute

Cache86400s public

chainethereumeipercstandardspecreference

API URLhttps://x402.hexl.dev/v1/chain/eip-lookup

Integration docs

Example request

{
  "number": 1559
}

Example response

{
  "number": 1559,
  "title": "Fee market change for ETH 1.0 chain",
  "author": "Vitalik Buterin (@vbuterin), Eric Conner (@econoar), Rick Dudley (@AFDudley), Matthew Slipper (@mslipper), Ian Norden (@i-norden), Abdelhamid Bakhta (@abdelhamidbakhta)",
  "status": "Final",
  "type": "Standards Track",
  "category": "Core",
  "created": "2019-04-13",
  "requires": [
    2718,
    2930
  ],
  "discussionsTo": "https://ethereum-magicians.org/t/eip-1559-fee-market-change-for-eth-1-0-chain/2783",
  "abstract": "We introduce a new [EIP-2718](./eip-2718.md) transaction type, with the format `0x02 || rlp([chain_id, nonce, max_priority_fee_per_gas, max_fee_per_gas, gas_limit, destination, amount, data, access_list, signature_y_parity, signature_r, signature_s])`.",
  "found": true,
  "repo": "ethereum/EIPs",
  "url": "https://eips.ethereum.org/EIPS/eip-1559"
}

Input schema

{
  "type": "object",
  "required": [
    "number"
  ],
  "properties": {
    "number": {
      "type": [
        "integer",
        "string"
      ],
      "description": "EIP/ERC number, e.g. 1559, 20, 4626."
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}