StorageQuery Precompile

Last updated: Aug 03, 2026

Provides raw read access to on-chain Substrate storage from within an EVM contract. Pass a SCALE-encoded storage key as calldata; receive the raw SCALE-encoded value.

The precompile is restricted to authorized pallet prefixes: SubtensorModule, Swap, Balances, Proxy, Scheduler, Drand, Crowdloan, Sudo, Multisig, Timestamp. Any key outside these prefixes returns an error.

Address: 0x0000000000000000000000000000000000000807
Source code: StorageQuery reference

Interface

The precompile does not use ABI-encoded calls — pass the raw storage key directly as calldata. For example:

import { ethers } from "ethers";

const STORAGE_QUERY_ADDRESS = "0x0000000000000000000000000000000000000807";

const provider = new ethers.JsonRpcProvider("YOUR_RPC_URL");

const KEYS = {
  TotalIssuance:
    "0x658faa385070e074c85bf6b568cf055557c875e4cff74148e4628f264b974c80",
  TotalNetworks:
    "0x658faa385070e074c85bf6b568cf05555f3bb7bcd0a076a48abf8c256d221721",
};

for (const [name, key] of Object.entries(KEYS)) {
  try {
    const raw = await provider.call({
      to: STORAGE_QUERY_ADDRESS,
      data: key,
    });
    console.log(`${name}`);
    console.log(`  key: ${key}`);
    console.log(`  raw: ${raw}`);
    // raw is SCALE-encoded — decode with @polkadot/api for human-readable values
  } catch (err) {
    console.log(`${name} error: ${err.message}`);
  }
}

when to use the StorageQuery precompile

Use StorageQuery when the value you need is not exposed by any typed precompile. For most use cases, prefer the typed precompiles (Metagraph, Alpha, Staking, etc.) — raw storage values are SCALE-encoded and require Substrate codec knowledge to decode on-chain.

Interface​

Interface