eth_getCode

eth_getCode returns the EVM bytecode deployed at an address on OP Mainnet, captured at whichever block you specify. Because OP Mainnet runs the OP Stack (Bedrock) and stays EVM-equivalent with Ethereum L1, the bytecode for a contract such as a Velodrome pool or a Synthetix module is identical in form to what you would read on L1, while gas is still paid in ETH. Point the request at https://optimism.therpc.io/YOUR_API_KEY (chain ID 10, 0xa). The response is the hex-encoded bytecode at the given address and block, or 0x when there is no code there.

Use cases

• Tell contract accounts from externally owned accounts on OP Mainnet by checking whether the result is 0x.
• Confirm a freshly deployed contract matches the expected bytecode after a Superchain deployment.
• Detect proxy contracts by spotting minimal-proxy (EIP-1167) or transparent/UUPS (EIP-1967) bytecode patterns.
• Audit whether a contract still has code at a historical block, revealing whether it was self-destructed.

Parameters

Response

Example request

1curl https://optimism.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "eth_getCode",
7    "params": [
8        "0x0000000000000000000000000000000000000000",
9        "latest"
10      ],
11    "id": 1
12  }'

Try it live in the Optimism playground.

Errors & troubleshooting

Common pitfalls

• A 0x result covers both EOAs and self-destructed contracts on OP Mainnet — absence of code alone does not tell you which case you hit.
• For a proxy, this returns the proxy's own bytecode, not the implementation's; resolve the implementation slot (e.g. via eth_getStorageAt) to read the logic contract.
• Querying an old block requires an archive node; on a pruned node a historical lookup fails with a missing trie node error.

Supported networks

• Mainnet — Chain ID: 10
• Sepolia — Chain ID: 11155420

See also

• eth_getStorageAt
• eth_getProof
• eth_call
• eth_getBalance

1curl https://optimism.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H 'Content-Type: application/json' \
4  -d '{"jsonrpc":"2.0","id":1,"method":"eth_getCode","params":["0x0000000000000000000000000000000000000000",""]}'