Optimism

Optimism JSON-RPC API

Standard Ethereum JSON-RPC method invocation.

Documentation GitHub OpenAPI

Operations 1

POST / Invoke a JSON-RPC method #

Specifications

⚙

OpenAPI

https://raw.githubusercontent.com/api-evangelist/optimism/refs/heads/main/openapi/optimism-json-rpc-api-openapi.yml

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OpenAPI Specification

openapi: 3.2.0
info:
  title: OP Mainnet JSON RPC API
  description: 'Public Ethereum JSON-RPC endpoint for OP Mainnet (chain ID 10) and the

    OP Sepolia testnet (chain ID 11155420). All standard Ethereum `eth_*`

    namespace methods are supported plus Optimism extensions used for L1

    fee estimation and rollup-specific data.


    All RPC calls are POSTed to the root path of the endpoint with a

    standard JSON-RPC 2.0 envelope. The public endpoints are open

    (unauthenticated) and rate limited; production teams typically route

    through Alchemy, QuickNode, Infura, or a self-hosted op-geth/op-node

    pair.

    '
  version: 1.0.0
  contact:
    name: Optimism
    url: https://docs.optimism.io
servers:
- url: https://mainnet.optimism.io
  description: OP Mainnet (chain ID 10) public RPC
- url: https://sepolia.optimism.io
  description: OP Sepolia (chain ID 11155420) public RPC
tags:
- name: JSON-RPC
  description: Standard Ethereum JSON-RPC method invocation.
paths:
  /:
    post:
      tags:
      - JSON-RPC
      summary: Invoke a JSON-RPC method
      description: 'Execute any supported Ethereum JSON-RPC method (e.g. `eth_blockNumber`,

        `eth_chainId`, `eth_getBalance`, `eth_call`, `eth_getTransactionByHash`,

        `eth_getLogs`, `net_version`, `web3_clientVersion`).

        '
      operationId: invokeJsonRpc
      requestBody:
        required: true
        content:
          application/json:
            schema:
              oneOf:
              - $ref: '#/components/schemas/JsonRpcRequest'
              - type: array
                items:
                  $ref: '#/components/schemas/JsonRpcRequest'
            examples:
              ethBlockNumber:
                summary: Get latest block number
                value:
                  jsonrpc: '2.0'
                  id: 1
                  method: eth_blockNumber
                  params: []
              ethChainId:
                summary: Get chain ID
                value:
                  jsonrpc: '2.0'
                  id: 2
                  method: eth_chainId
                  params: []
              ethGetBalance:
                summary: Get account balance
                value:
                  jsonrpc: '2.0'
                  id: 3
                  method: eth_getBalance
                  params:
                  - '0x0000000000000000000000000000000000000000'
                  - latest
              ethCall:
                summary: Read-only contract call
                value:
                  jsonrpc: '2.0'
                  id: 4
                  method: eth_call
                  params:
                  - to: '0x4200000000000000000000000000000000000006'
                    data: '0x06fdde03'
                  - latest
      responses:
        '200':
          description: JSON-RPC response (single or batch).
          content:
            application/json:
              schema:
                oneOf:
                - $ref: '#/components/schemas/JsonRpcResponse'
                - type: array
                  items:
                    $ref: '#/components/schemas/JsonRpcResponse'
        '429':
          description: Rate limit exceeded on the public endpoint.
components:
  schemas:
    JsonRpcResponse:
      type: object
      required:
      - jsonrpc
      - id
      properties:
        jsonrpc:
          type: string
          const: '2.0'
        id:
          oneOf:
          - type: string
          - type: integer
          - type: 'null'
        result:
          description: Method result; type depends on the method.
        error:
          $ref: '#/components/schemas/JsonRpcError'
    JsonRpcError:
      type: object
      required:
      - code
      - message
      properties:
        code:
          type: integer
        message:
          type: string
        data:
          description: Optional error data.
    JsonRpcRequest:
      type: object
      required:
      - jsonrpc
      - method
      - id
      properties:
        jsonrpc:
          type: string
          const: '2.0'
        id:
          oneOf:
          - type: string
          - type: integer
        method:
          type: string
          description: 'Name of the Ethereum JSON-RPC method, e.g. `eth_blockNumber`,

            `eth_chainId`, `eth_call`, `eth_getLogs`, `eth_getBalance`,

            `eth_sendRawTransaction`.

            '
        params:
          type: array
          items: {}
externalDocs:
  description: Optimism Superchain Networks Docs
  url: https://docs.optimism.io/superchain/networks