I need to know storage address of solidity smart contract variables before its deployment. how can I get this?

1 Answer 1


Which storage slots are allocated for which contract variable depends on the language and/or compiler. The Solidity compiler has an option to output the storage layout as a JSON structure:


In the Solidity language you can use .slot in assembly to get the storage slot of a variable:

pragma solidity 0.7.4;

contract StorageSlotFetch
    struct ThreeSlots
        uint256 a;
        uint256 b;
        uint256 c;
    address var0;
    uint256 var1;
    bytes32 var2;
    ThreeSlots var3;
    uint256 var4;
    function getStorageSlots() external pure returns (uint256[5] memory ret)
        assembly {
            mstore(add(ret,   0), var0.slot)
            mstore(add(ret,  32), var1.slot)
            mstore(add(ret,  64), var2.slot)
            mstore(add(ret,  96), var3.slot)
            mstore(add(ret, 128), var4.slot)

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge that you have read and understand our privacy policy and code of conduct.

Not the answer you're looking for? Browse other questions tagged or ask your own question.