eth_getStorageAt

eth_getStorageAt reads a single 32-byte word directly out of a contract's storage trie on Polygon. Every smart contract has a flat key→value storage space indexed by 256-bit slot numbers; this method returns the raw value at one slot, exactly as the EVM sees it, as a 0x-prefixed 32-byte hex string.

Use it to inspect contract state that no public getter exposes — for example, detecting and reading a proxy's implementation slot (EIP-1967), reading a token's packed balance/total state, or any internal variable once you have computed its slot. By varying the third parameter (the block tag) you can read the slot as of the latest block, a pending block, or any historical block height.

You are responsible for knowing the storage layout of the contract you query. Solidity assigns simple state variables to sequential slots starting at 0, while mapping and dynamic-array entries live at slots derived with keccak256. The method does no decoding: a slot that has never been written returns all-zeroes (0x0000…0000).

Positional params array: [address, storageSlot, blockTag].

Response fields

Errors are returned in the standard JSON-RPC envelope (error.code + error.message, with extra fields under error.data). See errors.md for the full envelope and shared codes.

JavaScript (fetch)

const res = await fetch("https://api.triport.io/polygon", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.TRIPORT_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    jsonrpc: "2.0",
    id: 1,
    method: "eth_getStorageAt",
    params: [
      "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174",
      "0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bba",
      "latest",
    ],
  }),
});


const { result } = await res.json();
console.log(result);                      // 0x0000...baf9
console.log("0x" + result.slice(-40));    // implementation address

TypeScript SDK (@triport/sdk)

import { Triport } from "@triport/sdk";


const client = new Triport({ apiKey: process.env.TRIPORT_API_KEY! });


const word = await client.polygon.getStorageAt(
  "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174",
  "0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bba",
  "latest",
);


console.log(word);                    // 0x0000...baf9
console.log("0x" + word.slice(-40));  // implementation address

Python (triport-sdk)

import os
from triport import Triport


client = Triport(api_key=os.environ["TRIPORT_API_KEY"])


word = client.polygon.get_storage_at(
    "0x2791Bca1f2de4661ED88A30C99A7a9449Aa84174",
    "0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bba",
    "latest",
)


print(word)                  # 0x0000...baf9
print("0x" + word[-40:])     # implementation address

• Proxy detection (EIP-1967). Polygon hosts many upgradeable proxy contracts (USDC.e, bridged assets, DeFi pools). Read slot 0x360894a13ba1a3210667c828492db98dca3e2076cc3735a920a3ca505d382bba — a non-zero result means the address is a proxy whose implementation lives in the lowest 20 bytes. Some older proxies instead keep the implementation at slot 0x0.
• You must compute mapping/array slots yourself. For a mapping(address => uint) at declared slot p, the entry for key k lives at keccak256(abi.encode(k, p)) — this is how you read an ERC-20 balance manually. Dynamic-array data starts at keccak256(p). Simple variables occupy slots 0, 1, 2, … in declaration order, with several small variables packed into one 32-byte slot.
• Raw bytes, no decoding. The result is always 32 bytes. Interpret it yourself — as a uint256, an address (lowest 20 bytes), a bool, or packed fields — based on the contract's storage layout.
• Block tags. pending reflects not-yet-mined state and may change; latest is the safest default. A 0x-prefixed hex block number reads historical storage (archive lookups).
• Related methods. To read return values of view functions instead of raw storage, call eth_call. To fetch a contract's bytecode, use eth_getCode; pairing it with eth_getStorageAt at slot 0x0 is a common proxy-unwrap pattern.
• Rate limits are enforced per second per tier (no daily cap). On -32003, honor the Retry-After header and use exponential backoff rather than retrying immediately.