Optimism Sepolia RPC endpoint
Optimism Sepolia (chain ID 11155420) is served over HTTPS POST JSON-RPC 2.0. Full and archive nodes back the endpoint, supporting standard EVM methods, historical state, trace_* methods, debug_* methods. Free, paid plans, and PAYG include Optimism Sepolia.
Network information
| Network | Optimism Sepolia |
| Chain ID | 11155420 |
| Endpoint | https://rpc.solidrpc.io/YOUR_API_KEY/evm/11155420 |
| Access | Free and paid |
| Type | Testnet · L2 |
| Native currency | ETH |
| Node types | Full + Archive |
| Methods | standard, trace, debug |
| Protocol | HTTPS JSON-RPC 2.0. WebSocket unavailable. WebSocket details |
Quickstart
Fetch the latest Optimism Sepolia block number. Replace YOUR_API_KEY with a key from the dashboard. New accounts start on the Free plan, no card required (see getting started):
curl https://rpc.solidrpc.io/YOUR_API_KEY/evm/11155420 \
-X POST \
-H "Content-Type: application/json" \
-d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'Archive access and tracing
There is no separate archive endpoint for Optimism Sepolia. Historical queries route to archive nodes automatically by block age, at no surcharge.
The debug_* tracing namespace is available:
curl https://rpc.solidrpc.io/YOUR_API_KEY/evm/11155420 \
-X POST \
-H "Content-Type: application/json" \
-d '{"jsonrpc":"2.0","method":"debug_traceTransaction","params":["0xTRANSACTION_HASH",{"tracer":"callTracer"}],"id":1}'Parity-style trace_* methods are also available.
Details on archive nodes and tracing.
Limits and errors
Quotas and rate limits are account-wide, not per-chain. Method calls to Optimism Sepolia draw from the same response-unit quota and rate limit as every other network. Error bodies are identical everywhere. See the error reference.