Free Optimism RPC Endpoint
Chain ID 10 · ETH · multi-region with automatic failover
Optimism (Chain ID 10) is an OP-Stack rollup secured by Ethereum and home of the Superchain. NodeFlare runs dedicated Optimism nodes with multi-region routing and automatic failover.
Public endpoint — no API key
HTTPS
https://rpc.nodeflare.app/op/publicWSS
wss://rpc.nodeflare.app/op/ws/publicNeed higher limits? Use a keyed endpoint https://rpc.nodeflare.app/op/v1/{YOUR_KEY} — get a free key →
Connect to Optimism
curl -s -X POST https://rpc.nodeflare.app/op/public \
-H 'content-type: application/json' \
-d '{"jsonrpc":"2.0","id":1,"method":"eth_blockNumber","params":[]}'import { ethers } from "ethers";
const provider = new ethers.JsonRpcProvider(
"https://rpc.nodeflare.app/op/public"
);
const block = await provider.getBlockNumber();import { createPublicClient, http } from "viem";
const client = createPublicClient({
transport: http("https://rpc.nodeflare.app/op/public"),
});
const block = await client.getBlockNumber();from web3 import Web3
w3 = Web3(Web3.HTTPProvider(
"https://rpc.nodeflare.app/op/public"
))
print(w3.eth.block_number)Add Optimism to your wallet
Network details for MetaMask, Rabby, or any EVM wallet — Optimism chain ID 10 (0xa).
| Network name | Optimism |
| RPC URL | https://rpc.nodeflare.app/op/public |
| Chain ID | 10 |
| Currency symbol | ETH |
| Block explorer | https://optimistic.etherscan.io |
Built for Optimism
Superchain apps, low-cost DeFi, and onchain governance on Optimism. Every request routes to the nearest healthy node, with automatic failover and no per-request throttling — the gaps public endpoints leave.
Dedicated Optimism RPC node — your own path, not a shared pool
NodeFlare runs its own dedicated Optimism node on bare-metal — not a reseller of Alchemy or Infura, and not a shared free-for-all pool. A free or paid key gives you a dedicated endpoint path with your own rate limits, no per-request throttling, and full access to heavy methods (eth_getLogs, trace_*, debug_*) — your own Optimism RPC without running the node yourself.
Optimism RPC — FAQ
What is Optimism's chain ID?
Optimism's chain ID is 10 (hex 0xa). Its native currency is ETH and its block explorer is optimistic.etherscan.io. You can connect with NodeFlare's free public RPC at https://rpc.nodeflare.app/op/public — no API key required.
How do I add Optimism to MetaMask?
In MetaMask, open the network menu → "Add a network" → "Add a network manually", then enter — Network name: Optimism; New RPC URL: https://rpc.nodeflare.app/op/public; Chain ID: 10; Currency symbol: ETH; Block explorer URL: https://optimistic.etherscan.io. Save, then switch to Optimism. The endpoint is free and needs no account.
What is the Optimism RPC URL?
NodeFlare's public Optimism RPC URL is https://rpc.nodeflare.app/op/public over HTTPS and wss://rpc.nodeflare.app/op/ws/public over WSS. No API key is required for the public endpoint.
Is the Optimism RPC free?
Yes. The public Optimism endpoint is free with no sign-up. A free API key unlocks higher rate limits, heavy methods, and a dedicated path — 2,000,000 compute units per month, no credit card.
What are the Optimism RPC rate limits?
The public endpoint is limited to 2 requests/second per IP. A free key gives 10 requests/second; paid plans scale to 500 req/s. Every plan includes all 22 supported chains.
Is NodeFlare a good Optimism RPC provider?
NodeFlare is an independent Optimism RPC provider that runs its own nodes — not a reseller or aggregator of third-party backends. The public endpoint is free with no sign-up; a free API key adds higher rate limits, WebSocket, and heavy methods (eth_getLogs, trace_*, debug_*) — 2,000,000 compute units per month, no credit card.
Is there a dedicated Optimism RPC node?
Yes. NodeFlare runs its own dedicated Optimism node(s), and every request is routed to the nearest healthy node with automatic failover. A free or paid key gives you a dedicated endpoint path with your own rate limits and full access to archive methods like eth_getLogs and debug_traceTransaction.
Go deeper
- Full Optimism API reference → — supported methods, WebSocket, regions
- Rate limits & compute-unit costs → — what each method costs against your quota
- Pay per request with x402 → — Optimism calls in USDC from $0.001, no account:
POST /op/x402 - RPC for trading bots → and indexers → — low-latency, eth_getLogs-heavy workloads
- Screen a Optimism token for scams → — ownership, honeypot check, holder concentration → one risk score
- Onchain tools for AI agents → — token-safety, wallet intelligence and RPC over MCP / x402
Build on Optimism with a free key
Higher limits, a dedicated path, and automatic failover — every chain included. No credit card.
Get your free API key →Optimism RPC methods
Per-method docs for Optimism — parameters, compute-unit cost, and copy-paste examples.