Optimism
Optimism is an EVM rollup in the Gateway catalog with ETH as its gas token. Both of its networks are reachable over EVM JSON-RPC through a Gateway Access Point.
Networks and hosts
| Network | Chain ID | JSON-RPC Host |
|---|---|---|
| Mainnet | 10 | op-jsonrpc |
| Sepolia | 11155420 | op-sepolia-jsonrpc |
Optimism Sepolia (11155420) and Base Sepolia (84532) are distinct networks with distinct Gateways, so confirm the chain ID before pointing a client at an Access Point.
Provider coverage
| Provider | Mainnet | Sepolia | Generated URL form |
|---|---|---|---|
| Alchemy | Yes | Yes | https://<network-subdomain>.g.alchemy.com/v2 |
| QuickNode | Yes | Yes | The URL QuickNode already issued for the Endpoint |
| Chainstack | Yes | Yes | The node’s HTTPS endpoint |
| dRPC | Yes | Yes | https://lb.drpc.live/<network>/ |
| Tenderly | Yes | Yes | https://<network-slug>.gateway.tenderly.co |
Every one of these applies its credential as a path segment, so treat the effective Endpoint URL as a secret.
Reads without an Endpoint
The shared cache answers eth_blockNumber, eth_getBlockByNumber with ["latest", false] or an explicit hexadecimal height and false, and debug_traceBlockByNumber with the callTracer configuration. Other parameter variants and writes go to the Route. See Endpoint-free RPC for the exact forms and cache behavior.
Verify the network
curl '<optimism_access_point>' \
-H 'Authorization: Bearer <app_api_key>' \
-H 'Content-Type: application/json' \
--data '{"jsonrpc":"2.0","id":1,"method":"eth_chainId","params":[]}'Mainnet returns 0xa; Sepolia returns 0xaa37dc.
Coverage boundary
One JSON-RPC 2.0 object per HTTP POST. Optimism-specific namespaces, trace output, and historical state depend on the upstream node’s software and plan.
See Routing and reliability for the routing model and JSON-RPC for request format.