programSubscribe

Subscribe to a program to receive notifications when the lamports or data for an account owned by the given program changes.

Endpoints

Websockets are available on mainnet and devnet with the following URLs:

• Mainnet wss://mainnet.helius-rpc.com/?api-key=<API_KEY>
• Devnet wss://devnet.helius-rpc.com/?api-key=<API_KEY>

Websockets have a 10-minute inactivity timer; implementing health checks and sending pings every minute is heavily recommended to keep the websocket connection alive.

Authorizations

api-key · string · required

Your Helius API key. You can get one for free in the dashboard.

Body

params · array · required

Hide properties

programId · string · required

Pubkey of the program_id, as base-58 encoded string.

config · object

Configuration object containing the following fields:

commitment · string

The commitment level for the subscription. Can be finalized, confirmed, or processed.

filters · array

Array of filter objects to apply.

encoding · string

Encoding format for account data. Can be base58, base64, base64+zstd, or jsonParsed.

• base58 is slow
• jsonParsed encoding attempts to use program-specific state parsers to return more human-readable and explicit account state data
• If jsonParsed is requested but a parser cannot be found, the field falls back to binary encoding, detectable when the data field is type string.

Response

result · integer

Subscription id (needed to unsubscribe)

Notification Format

The notification format is a single program account object as seen in the getProgramAccounts RPC HTTP method.

Request

{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "programSubscribe",
  "params": [
    "11111111111111111111111111111111",
    {
      "encoding": "base64",
      "filters": [{ "dataSize": 80 }]
    }
  ]
}

Response

{
  "jsonrpc": "2.0",
  "result": 24040,
  "id": 1
}