eth_getStorageAt

eth_getStorageAt reads the raw 32-byte value held at a single storage slot of a contract, letting you inspect state that no public view function exposes. Base runs a standard EVM as Coinbase's OP Stack optimistic rollup that settles to Ethereum L1 and pays gas in ETH, so its storage layout follows the same Solidity slot rules as Ethereum mainnet. Point the call at https://base.therpc.io/YOUR_API_KEY (chain ID 8453, hex 0x2105) with a contract address, a slot index, and a block tag. The result is the 32-byte value at that slot, hex-encoded and left-padded with zeros.

Use cases

• Read the implementation address behind an upgradeable proxy from the EIP-1967 slot without needing the proxy's ABI — common for proxied apps deployed on Base.
• Inspect governance state directly, such as a proposal's status or vote tallies, when the contract keeps it in storage rather than a getter.
• Verify a deployed contract's storage layout during an audit by reading known slots and comparing against the source.
• Debug unexpected on-chain state by pulling the raw slot value at a specific Base block to see exactly what was written.

Parameters

Response

Example request

1curl https://base.therpc.io/YOUR_API_KEY \
2  -X POST \
3  -H "Content-Type: application/json" \
4  -d '{
5    "jsonrpc": "2.0",
6    "method": "eth_getStorageAt",
7    "params": [
8        "0x0000000000000000000000000000000000000000",
9        "0x0",
10        "latest"
11      ],
12    "id": 1
13  }'

Try it live in the Base playground.

Errors & troubleshooting

Common pitfalls

• Solidity storage layout is not part of the ABI, so you must know or derive the slot index for each variable — the same as on Ethereum, since Base uses the identical EVM layout rules.
• Several small variables can be packed into one 32-byte slot; pulling out a single field means masking and shifting the bytes you want.
• Mapping entries are not at the declared base slot — the value for a key lives at keccak256(abi.encode(key, baseSlot)), so compute that hash before reading.

Supported networks

• Mainnet — Chain ID: 8453
• Sepolia — Chain ID: 84532

See also

• eth_getCode
• eth_getProof
• eth_call

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