state_getKeysPaged

Description

Retrieves storage keys for a given prefix in pages. Ideal for scanning large maps such as System.Account, SALP voucher registries, or omnipool asset lists.

Parameters

Parameter	Type	Required	Description
prefix	string	Yes	Hex-encoded storage key prefix
count	number	Yes	Maximum number of keys to return
startKey	string	No	Start key for pagination
blockHash	string	No	Block hash for historical queries

Returns

Array of up to count storage keys.

Request Example

{
  "jsonrpc": "2.0",
  "method": "state_getKeysPaged",
  "params": [
    "0x26aa394eea5630e07c48ae0c9558cef7",
    100,
    null
  ],
  "id": 1
}

Response Example

{
  "jsonrpc": "2.0",
  "result": [
    "0x26aa394eea5630e07c48ae0c9558cef7b6a7c9a35a95a160cb4cad330558dfa56d6f646c755b98a7afd0913860592153322b957be394a0619f20b32679ac1014",
    "0x26aa394eea5630e07c48ae0c9558cef70d54f7f0e87470baa5944a45e66a77be5e2ff2b41d89577e728343f47e19f538d684125029b82546b86f1d7dc1c4bd2d"
  ],
  "id": 1
}

Code Examples

JavaScript

async function walkAccounts(pageSize = 256) {
  let startKey = null;
  const prefix = api.registry.createType('StorageKey', 'System', 'Account').toHex();

  while (true) {
    const keys = await api.rpc.state.getKeysPaged(prefix, pageSize, startKey);
    if (!keys.length) break;

    for (const key of keys) {
      // process key
    }

    startKey = keys[keys.length - 1];
  }
}

Python

prefix = '0x26aa394eea5630e07c48ae0c9558cef7'
start_key = None

while True:
    result = substrate.rpc_request(
        method='state_getKeysPaged',
        params=[prefix, 128, start_key]
    )["result"]
    if not result:
        break
    start_key = result[-1]

Tips

• Keep count ≤ 1000 to avoid large responses. Increase gradually based on latency and payload size.
• For parity with historical calculations, pass the finalized block hash rather than leaving it null.