eth_getStorageAt - Arbitrum - Alchemy Documentation

Arbitrum API - Returns the value from a storage position at a given address, or in other words, returns the state of the contract's storage, which may not be exposed via the contract's methods.

Parameters
DATA, 20 Bytes - address of the storage.
QUANTITY - integer of the position in the storage.
QUANTITY|TAG - integer block number, or the string "latest", "earliest" or "pending", see the default block parameter.
Returns
DATA - the value at this storage position.
Example
​Alchemy Composer​
The Alchemy Composer allows you to make a no-code example request via your browser. Try it out above!
Result
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{
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    "jsonrpc":"2.0",
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    "id":1,
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    "result":"0x00000000000000000000000000000000000000000000000000000000000004d2"
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}
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Retrieving an element of the map is harder. The position of an element in the map is calculated with:
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keccack(LeftPad32(key, 0), LeftPad32(map position, 0))
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This means to retrieve the storage on pos1[“0x391694e7e0b0cce554cb130d723a9d27458f9298”] we need to calculate the position with:
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keccak(decodeHex("000000000000000000000000391694e7e0b0cce554cb130d723a9d27458f9298" + "0000000000000000000000000000000000000000000000000000000000000001"))
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The geth console which comes with the web3 library can be used to make the calculation:
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> var key = "000000000000000000000000391694e7e0b0cce554cb130d723a9d27458f9298" + "0000000000000000000000000000000000000000000000000000000000000001"
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undefined
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> web3.sha3(key, {"encoding": "hex"})
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"0x6661e9d6d8b923d5bbaab1b96e1dd51ff6ea2a93520fdc9eb75d059238b8c5e9"
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Now to fetch the storage:
​Request​
Curl
Postman
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curl https://arb-mainnet.g.alchemy.com/v2/your-api-key \
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-X POST \
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-H "Content-Type: application/json" \
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-d '{"jsonrpc":"2.0", "method": "eth_getStorageAt", "params": ["0x295a70b2de5e3953354a6a8344e616ed314d7251", "0x6661e9d6d8b923d5bbaab1b96e1dd51ff6ea2a93520fdc9eb75d059238b8c5e9", "latest"], "id": 1}'
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URL: https://arb-mainnet.g.alchemy.com/v2/your-api-key
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RequestType: POST
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Body: 
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{
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    "jsonrpc":"2.0",
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    "method":"eth_getStorageAt",
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    "params":["0x295a70b2de5e3953354a6a8344e616ed314d7251", "0x6661e9d6d8b923d5bbaab1b96e1dd51ff6ea2a93520fdc9eb75d059238b8c5e9", "latest"],
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    "id":1
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}
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Result
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{
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    "jsonrpc":"2.0",
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    "id":1,
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    "result":"0x000000000000000000000000000000000000000000000000000000000000162e"
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}
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Arbitrum API
Alchemy Documentation