Storage Slot Layout Inspector

WHAT IT DOES

Storage Slot Layout Inspector is a read-only developer tool that inspects storage slot values of any deployed contract. It reads the contract address, storage slot numbers (user-provided), contract bytecode, storage values at the specified slots, and previous inspection records. The tool then displays the raw storage data for each slot, helping developers understand how contract state is stored and debug issues related to storage layout, such as proxy pattern storage collisions or manual storage manipulation.

HOW TO USE

Connect your wallet via the built-in connector. Select the network where the contract is deployed. Enter the contract address and a comma-separated list of storage slot numbers (e.g., "0,1,2,3"). The tool will read on-chain data and display a preview including: contract address, contract bytecode (truncated), whether the address is a contract, a list of storage slots with their raw values (truncated for readability), and previous inspection records. No transaction is signed or sent—this is a read-only inspection.

TECHNICAL MECHANISM

The tool uses ethers.js v5.7.2 to read contract data. It fetches the contract bytecode using `provider.getCode(contractAddress)` to confirm the address is a contract. For each storage slot, it uses `provider.getStorageAt(contractAddress, slotNumber)` to read the raw 32-byte value stored at that slot. The tool supports slot numbers as integers (e.g., 0, 1, 2) or hex strings (e.g., "0x0", "0x1"). It displays the values as hex strings. If the contract is a proxy (ERC-1967), slot 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bbc is the implementation slot, and slot 0xb53127684a568b3173ae13b9f8a6016e243e63b6e8ee1178d6a717850b5d6103 is the admin slot. However, the tool does not automatically interpret these—it displays the raw values for you to analyze. All reads are performed through the user's connected wallet provider—no centralized APIs are used. The tool does not store any inspection results; they are only displayed in the UI.

WHAT IT CANNOT SEE

This tool cannot verify that the storage slot layout is accurate—it reads raw values without context. It cannot detect if the contract uses upgradeable patterns that change storage layout. It cannot guarantee that storage values are correct—they are read from the current state. It cannot ensure that the slot numbers are valid—you must know the contract's storage layout. It cannot validate that the bytecode matches the source. It cannot detect if the contract has been modified. It cannot verify that the storage layout is reproducible. It cannot predict if storage slots will change in future versions.

PLEASE NOTE

This tool is EVM-only and works across all supported chains (Ethereum, Polygon, BNB Chain, Arbitrum, Optimism, Avalanche). The inspection is performed on the currently connected network—to inspect contracts on different chains, you must switch networks. The tool does not store or transmit any inspection data. Always interpret storage values with knowledge of the contract's storage layout—the raw values are meaningless without context.