Optimism (OP)

Optimism Network API Reference for efficient interaction with OP nodes, enabling scalable, low-cost transactions and fast finality through Layer 2 solutions on the Ethereum blockchain.

Optimism is a Layer 2 scaling solution for Ethereum that uses Optimistic Rollup technology to achieve high throughput and low transaction costs while inheriting Ethereum's security. Developed by the Optimism Collective, it enables near-instant transactions by executing them off-chain and posting compressed transaction data to Ethereum mainnet. The network is EVM-equivalent, meaning existing Ethereum smart contracts and tools work seamlessly without modification.

Key Features

• EVM Equivalence: Full compatibility with Ethereum Virtual Machine, allowing direct deployment of existing Solidity contracts

• Optimistic Rollups: Transactions are assumed valid by default, with a 7-day challenge period for fraud proofs

• Low Transaction Fees: Fees typically 10-100x lower than Ethereum mainnet

• Fast Transactions: Near-instant transaction confirmations (~2 second block time)

• Ethereum Security: Inherits security from Ethereum L1 through data availability and fraud proofs

• OP Token: Native governance token for the Optimism Collective

• Superchain Vision: Part of the broader Superchain ecosystem with shared security and interoperability

• Bedrock Upgrade: Latest architecture providing improved performance and EVM equivalence

• Developer-Friendly: Compatible with MetaMask, Hardhat, Foundry, and all standard Ethereum tools

TECHNICAL DISCLAIMER: AUTHORITATIVE JSON-RPC API SPECIFICATION.

GetBlock's RPC API reference documentation is provided exclusively for informational purposes and to optimize the developer experience. The canonical and normative specification for Ethereum Virtual Machine (EVM) JSON-RPC methods is solely maintained and published through the official Ethereum Foundation documentation portal at ethereum.org. For Optimism-specific methods, refer to the official Optimism documentation at docs.optimism.io.

Network Information

Property	Value
Network Name	Optimism Mainnet
Chain ID	10
Native Currency	ETH
Decimals	18
Block Time	~2 seconds
Consensus	Optimistic Rollup
EVM Compatible	Yes (EVM Equivalent)
L1 Settlement	Ethereum Mainnet

Base URL

Frankfurt, Germany

https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/

Supported Networks

Network	Chain ID	JSON-RPC	WSS	Frankfurt, Germany	GraphQL
Mainnet	10	✅	✅	✅	✅
Sepolia Testnet	11155420	✅	✅	✅	❌

Quickstart

Javascript(Axios)

1

Setup project

Create and initialize a new project:

mkdir optimism-api-quickstart
cd optimism-api-quickstart
npm init --yes

2

Install Axios

npm install axios

3

Create file

Create a new file named index.js. This is where you will make your first call.

4

Set ES module type

Set the ES module "type": "module" in your package.json.

5

Add code

Add the following code to index.js:

index.js

import axios from 'axios'
let data = JSON.stringify({
  jsonrpc: "2.0",
  method: "eth_blockNumber",
  params: [],
  id: "getblock.io",
});

let config = {
  method: "post",
  maxBodyLength: Infinity,
  url: "https://shared.us-east-1.getblock.io/<ACCESS_TOKEN>",
  headers: {
    "Content-Type": "application/json",
  },
  data: data,
};

axios
  .request(config)
  .then((response) => {
    console.log(JSON.stringify(response.data));
  })
  .catch((error) => {
    console.log(error);
  });

Replace <ACCESS-TOKEN> with your actual access token from GetBlock.

6

Run the script

node index.js

Expected output (example):

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "0x907de6b"
}

Python(Request)

1

Set up the project directory

mkdir optimism-api-quickstart
cd optimism-api-quickstart

2

Create and activate a virtual environment

python -m venv venv
source venv/bin/activate

# On Windows, 
use venv\Scripts\activate

3

Install requests

pip install requests

4

Create script

Create a file called main.py with the following content:

main.py

import requests
import json

url = "https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/"

payload = json.dumps({
    "jsonrpc": "2.0",
    "method": "eth_blockNumber",
    "params": [],
    "id": "getblock.io"
})

headers = {
    'Content-Type': 'application/json'
}

response = requests.post(url, headers=headers, data=payload)
print(response.text)

Replace <ACCESS-TOKEN> with your actual access token from GetBlock.

5

Run the script

python main.py

Available API Methods

Account/State Methods

Method	Description
eth_accounts	Returns addresses owned by client
eth_getBalance	Returns the ETH balance of an address
eth_getStorageAt	Returns the value at a storage position
eth_getCode	Returns the bytecode at an address
eth_getProof	Returns account and storage Merkle proofs
eth_call	Executes a call without creating a transaction

Block Methods

Method	Description
eth_blockNumber	Returns the current block number
eth_getBlockByHash	Returns block information by hash
eth_getBlockByNumber	Returns block information by number
eth_getBlockTransactionCountByHash	Returns transaction count in a block by hash
eth_getBlockTransactionCountByNumber	Returns transaction count in a block by number

Transaction Methods

Method	Description
eth_sendRawTransaction	Submits a signed transaction to the network
eth_getTransactionByHash	Returns transaction details by hash
eth_getTransactionByBlockHashAndIndex	Returns transaction by block hash and index
eth_getTransactionByBlockNumberAndIndex	Returns transaction by block number and index
eth_getTransactionCount	Returns the nonce (transaction count) for an address
eth_getTransactionReceipt	Returns the receipt of a mined transaction

Gas Methods

Method	Description
eth_gasPrice	Returns the current L2 gas price in wei
eth_estimateGas	Estimates gas needed for a transaction

Filter Methods

Method	Description
eth_getLogs	Returns logs matching filter criteria
eth_newFilter	Creates a new log filter
eth_newBlockFilter	Creates a filter for new blocks
eth_newPendingTransactionFilter	Creates a filter for pending transactions
eth_getFilterChanges	Returns filter changes since last poll
eth_getFilterLogs	Returns all logs matching filter
eth_uninstallFilter	Removes an existing filter

Subscription Methods (WebSocket)

Method	Description
eth_subscribe	Creates a subscription for events
eth_unsubscribe	Cancels an existing subscription

Uncle Methods

Method	Description
eth_getUncleByBlockHashAndIndex	Returns uncle block by hash and index
eth_getUncleByBlockNumberAndIndex	Returns uncle block by number and index
eth_getUncleCountByBlockHash	Returns uncle count in a block by hash
eth_getUncleCountByBlockNumber	Returns uncle count in a block by number

Network/Chain Methods

Method	Description
eth_chainId	Returns the chain ID (10)
eth_syncing	Returns sync status of the node
net_version	Returns the network ID
net_listening	Returns listening status
net_peerCount	Returns number of connected peers
web3_clientVersion	Returns the client version
web3_sha3	Returns Keccak-256 hash of data
rpc_modules	Returns enabled RPC modules

Support

For technical support and questions:

• Support: [e-mail]

See Also

• Optimism Documentation

• Optimism Block Explorer (Optimistic Etherscan)

• Optimism Bridge

• Ethereum JSON-RPC Specification

• Optimism Website