> ## Documentation Index
> Fetch the complete documentation index at: https://www.helius.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Subscribe

> Subscribe to accounts, transactions, blocks, and slot updates to receive real-time notifications using the high-performance gRPC API.

<hide>
  ## Endpoints

  gRPC services are available on mainnet and devnet with the following URLs:

  * **Mainnet** `https://laserstream-mainnet.helius-rpc.com:443`
  * **Devnet** `https://laserstream-devnet.helius-rpc.com:443`
</hide>

## Authorizations

<ParamField query="x-token" type="string" required>
  Your Helius API key. You can get one for free in the
  [dashboard](https://dashboard.helius.dev/api-keys).
</ParamField>

## Message

The gRPC API supports multiple subscription types that can be combined in a single request:

<ParamField body="accounts" type="object">
  Subscribe to account updates. Returns data when specified accounts are
  modified.

  <Expandable title="properties" defaultOpen>
    <ParamField body="account" type="array">
      Array of account pubkeys to monitor.
    </ParamField>

    <ParamField body="owner" type="array">
      Array of owner pubkeys to monitor (all accounts owned by these programs).
    </ParamField>

    <ParamField body="filters" type="object">
      Optional filters to apply.

      <Expandable title="filter options">
        <ParamField body="memcmp" type="object">
          Filter by specific bytes at an offset in account data.

          <Expandable title="properties">
            <ParamField body="offset" type="integer">
              Position in bytes to start comparing data.
            </ParamField>

            <ParamField body="bytes" type="string">
              The data to compare against (bytes format).
            </ParamField>

            <ParamField body="base58" type="string">
              The data to compare against (base58 format).
            </ParamField>

            <ParamField body="base64" type="string">
              The data to compare against (base64 format).
            </ParamField>
          </Expandable>
        </ParamField>

        <ParamField body="datasize" type="integer">
          Filter by exact account data size in bytes.
        </ParamField>

        <ParamField body="token_account_state" type="boolean">
          Filter to only token accounts.
        </ParamField>

        <ParamField body="lamports" type="object">
          Filter by SOL balance with comparisons.

          <Expandable title="comparison operators">
            <ParamField body="eq" type="integer">
              Equal to specified amount.
            </ParamField>

            <ParamField body="ne" type="integer">
              Not equal to specified amount.
            </ParamField>

            <ParamField body="lt" type="integer">
              Less than specified amount.
            </ParamField>

            <ParamField body="gt" type="integer">
              Greater than specified amount.
            </ParamField>
          </Expandable>
        </ParamField>
      </Expandable>
    </ParamField>

    <ParamField body="nonempty_txn_signature" type="boolean">
      If `true`, only include updates caused by a transaction. If `false`, only include updates not caused by a transaction. If `undefined`, include all updates.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="slots" type="object">
  Subscribe to slot updates.

  <Expandable title="properties" defaultOpen>
    <ParamField body="filter_by_commitment" type="boolean">
      Filter slots by commitment level.
    </ParamField>

    <ParamField body="interslot_updates" type="boolean">
      Include intermediate slot status updates (PROCESSED, CONFIRMED, FINALIZED,
      FIRST\_SHRED\_RECEIVED, COMPLETED, CREATED\_BANK, DEAD).
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="transactions" type="object">
  Subscribe to transaction updates.

  <Expandable title="properties" defaultOpen>
    <ParamField body="vote" type="boolean">
      Include vote transactions.
    </ParamField>

    <ParamField body="failed" type="boolean">
      Include failed transactions.
    </ParamField>

    <ParamField body="signature" type="string">
      Monitor specific transaction signature.
    </ParamField>

    <ParamField body="account_include" type="array">
      Only include transactions affecting these accounts.
    </ParamField>

    <ParamField body="account_exclude" type="array">
      Exclude transactions affecting these accounts.
    </ParamField>

    <ParamField body="account_required" type="array">
      Transactions must affect all of these accounts.
    </ParamField>

    <ParamField body="token_accounts" type="enum">
      Optional associated token account (ATA) expansion (field tag 30, `TokenAccountExpansionControlFlag`). When set, an `account_include` wallet also matches transactions where it **owns** an SPL token balance — for example, incoming token transfers that touch the wallet's token account rather than its pubkey. Two variants:

      * `ALL` (**0**) — match any transaction referencing a token balance the wallet owns, even if unchanged. Higher volume.
      * `BALANCE_CHANGED` (**1**) — match when the wallet owns a token balance whose amount changed (or whose token account was closed) in the transaction.

      To disable expansion, **leave the field absent** (`None`) — there is no "off" enum value. An out-of-range integer is rejected at config build: `Invalid token_accounts value, expected ALL (0) or BALANCE_CHANGED (1)`.

      <Warning>
        `ALL` is the **zero value**. A client that sets the enum to `0` expecting "default/off" gets `ALL` — the broadest, highest-volume mode. The only way to mean "no expansion" is to omit the field entirely.
      </Warning>
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="transactions_status" type="object">
  Subscribe to transaction status updates.

  <Expandable title="properties" defaultOpen>
    <ParamField body="vote" type="boolean">
      Include vote transactions.
    </ParamField>

    <ParamField body="failed" type="boolean">
      Include failed transactions.
    </ParamField>

    <ParamField body="signature" type="string">
      Monitor specific transaction signature.
    </ParamField>

    <ParamField body="account_include" type="array">
      Only include transactions affecting these accounts.
    </ParamField>

    <ParamField body="account_exclude" type="array">
      Exclude transactions affecting these accounts.
    </ParamField>

    <ParamField body="account_required" type="array">
      Transactions must affect all of these accounts.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="blocks" type="object">
  Subscribe to block updates.

  <Expandable title="properties" defaultOpen>
    <ParamField body="account_include" type="array">
      Only include blocks with transactions affecting these accounts.
    </ParamField>

    <ParamField body="include_transactions" type="boolean">
      Include full transaction details.
    </ParamField>

    <ParamField body="include_accounts" type="boolean">
      Include account updates.
    </ParamField>

    <ParamField body="include_entries" type="boolean">
      Include block entries.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="blocks_meta" type="object">
  Subscribe to block metadata updates (lighter than full block updates).

  <Expandable title="returns" defaultOpen>
    <ParamField body="slot" type="integer">
      Slot number.
    </ParamField>

    <ParamField body="blockhash" type="string">
      Blockhash.
    </ParamField>

    <ParamField body="rewards" type="array">
      Rewards information.
    </ParamField>

    <ParamField body="block_time" type="integer">
      Block time.
    </ParamField>

    <ParamField body="block_height" type="integer">
      Block height.
    </ParamField>

    <ParamField body="parent_slot" type="integer">
      Parent slot.
    </ParamField>

    <ParamField body="parent_blockhash" type="string">
      Parent blockhash.
    </ParamField>

    <ParamField body="executed_transaction_count" type="integer">
      Transaction count.
    </ParamField>

    <ParamField body="entries_count" type="integer">
      Entry count.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="entry" type="object">
  Subscribe to entry updates.

  <Expandable title="returns" defaultOpen>
    <ParamField body="slot" type="integer">
      Slot number.
    </ParamField>

    <ParamField body="index" type="integer">
      Entry index.
    </ParamField>

    <ParamField body="num_hashes" type="integer">
      Number of hashes.
    </ParamField>

    <ParamField body="hash" type="string">
      Hash.
    </ParamField>

    <ParamField body="executed_transaction_count" type="integer">
      Transaction count.
    </ParamField>

    <ParamField body="starting_transaction_index" type="integer">
      Starting transaction index.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="commitment" type="enum">
  The commitment level for the subscription:

  <Expandable title="levels" defaultOpen>
    <ParamField body="PROCESSED" type="integer">
      (0): Processed by the current node.
    </ParamField>

    <ParamField body="CONFIRMED" type="integer">
      (1): Confirmed by supermajority of the cluster.
    </ParamField>

    <ParamField body="FINALIZED" type="integer">
      (2): Finalized by the cluster.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="accounts_data_slice" type="array">
  Specifies partial account data to receive:

  <Expandable title="properties" defaultOpen>
    <ParamField body="offset" type="integer">
      Position in bytes to start reading data.
    </ParamField>

    <ParamField body="length" type="integer">
      Number of bytes to read.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="ping" type="object">
  Enable ping-pong messages for connection health monitoring.

  <Expandable title="properties" defaultOpen>
    <ParamField body="id" type="integer">
      Numeric identifier for the ping.
    </ParamField>
  </Expandable>
</ParamField>

<ParamField body="from_slot" type="integer">
  Starting slot to receive updates from. Updates for slots before this value
  will be excluded.
</ParamField>

<RequestExample>
  ```json Accounts Subscription theme={"system"}
  {
    "slots": {
        "slots": {}
    },
    "accounts": {
        "user-defined-label": {
            "account": [
                "DjUF9ASpyMbVpGJmTvzfSbCgUWj6JowwLh8dGAJzSPmu",
                "5U3bH5b6XtG99aVCE9ycvDgBKQx3fVT8WwTNbMToFuEr"
            ],
            "owner": [
                "TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"
            ],
            "filter": {
                "memcmp": {
                    "offset": 0,
                    "bytes": "0102030405"
                },
                "datasize": 165,
                "token_account_state": true,
                "lamports": {
                    "gt": 100000000
                }
            },
            "nonempty_txn_signature": true
        }
    },
    "transactions": {},
    "blocks": {},
    "blocks_meta": {},
    "accounts_data_slice": [],
    "commitment": 1
  }
  ```

  ```json Slots Subscription theme={"system"}
  {
    "slots": {
      "incoming_slots": {}
    },
    "commitment": 1
  }
  ```

  ```json Transactions Subscription theme={"system"}
  {
    "transactions": {
      "vote": false,
      "failed": true,
      "signature": "4RPMxKBhCBubFmZ1r9BC52ztjG3qBTW9Gp1PXfufUSATQaLKTW3Dj6vQBYyVrhfjgJ4PjZLzwYs4Z92KDCPw8Qym",
      "account_include": ["DjUF9ASpyMbVpGJmTvzfSbCgUWj6JowwLh8dGAJzSPmu"],
      "account_exclude": ["TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"],
      "account_required": ["11111111111111111111111111111111"]
    },
    "commitment": 2
  }
  ```

  ```json Wallet + Token Transfers (ATA expansion) theme={"system"}
  {
    "transactions": {
      "wallet": {
        "vote": false,
        "failed": false,
        "account_include": ["DjUF9ASpyMbVpGJmTvzfSbCgUWj6JowwLh8dGAJzSPmu"],
        "account_exclude": [],
        "account_required": [],
        "token_accounts": 1
      }
    },
    "commitment": 1
  }
  ```

  ```json Transaction Status Subscription theme={"system"}
  {
    "transactions_status": {
      "vote": false,
      "failed": true,
      "account_include": ["DjUF9ASpyMbVpGJmTvzfSbCgUWj6JowwLh8dGAJzSPmu"],
      "account_exclude": ["TokenkegQfeZyiNwAJbNbGKPFXCWuBvf9Ss623VQ5DA"],
      "account_required": ["11111111111111111111111111111111"]
    },
    "commitment": 2
  }
  ```

  ```json Blocks Subscription theme={"system"}
  {
    "blocks": {
      "account_include": ["DjUF9ASpyMbVpGJmTvzfSbCgUWj6JowwLh8dGAJzSPmu"],
      "include_transactions": 1,
      "include_accounts": 1,
      "include_entries": 0
    },
    "commitment": 2
  }
  ```

  ```json Block Metadata Subscription theme={"system"}
  {
    "blocks_meta": {},
    "commitment": 2,
    "from_slot": 139000000
  }
  ```

  ```json Entry Subscription theme={"system"}
  {
    "entry": {},
    "commitment": 1
  }
  ```

  ```json Partial Account Data Subscription theme={"system"}
  {
    "accounts": {
      "account": ["DjUF9ASpyMbVpGJmTvzfSbCgUWj6JowwLh8dGAJzSPmu"]
    },
    "accounts_data_slice": [
      {
        "offset": 0,
        "length": 64
      },
      {
        "offset": 128,
        "length": 32
      }
    ],
    "commitment": 2
  }
  ```

  ```json Ping Subscription theme={"system"}
  {
    "ping": {
      "id": 1
    }
  }
  ```

  ```json Combined Subscription theme={"system"}
  {
    "accounts": {
      "account": ["DjUF9ASpyMbVpGJmTvzfSbCgUWj6JowwLh8dGAJzSPmu"],
      "nonempty_txn_signature": true
    },
    "slots": {
      "filter_by_commitment": 1,
      "interslot_updates": 1
    },
    "commitment": 2,
    "from_slot": 139000000,
    "ping": {
      "id": 123
    }
  }
  ```
</RequestExample>

## Commitment Levels

All subscriptions support the following commitment levels:

* `PROCESSED`: Processed by the current node (0)
* `CONFIRMED`: Confirmed by supermajority of the cluster (1)
* `FINALIZED`: Finalized by the cluster (2)

## Response Structure

Subscription responses include:

* `filters`: The filter names that matched this update
* One of the following update types:
  * `account`: Account data, owner, lamports, executable status, etc.
  * `slot`: Slot information and status updates
  * `transaction`: Full transaction details, signature, and metadata
  * `transaction_status`: Transaction execution status (success/error)
  * `block`: Complete block data with transactions, accounts, rewards, etc.
  * `block_meta`: Lightweight block metadata without full transaction details
  * `entry`: Entry details within a block
  * `ping`/`pong`: Connection health check messages
* `created_at`: Timestamp when the update was created

<ResponseExample>
  ```json Account Update theme={"system"}
  {
    "filters": ["accounts"],
    "account": {
      "account": {
        "pubkey": "BASE58_ENCODED_PUBKEY",
        "lamports": 12345678,
        "owner": "BASE58_ENCODED_OWNER",
        "executable": false,
        "rent_epoch": 361,
        "data": "BASE64_ENCODED_DATA",
        "write_version": 123,
        "txn_signature": "BASE58_ENCODED_SIGNATURE"
      },
      "slot": 189554321,
      "is_startup": false
    },
    "created_at": "2023-04-28T12:34:56.789Z"
  }
  ```

  ```json Slot Update theme={"system"}
  {
    "filters": ["slots"],
    "slot": {
      "slot": 189554321,
      "parent": 189554320,
      "status": 2,
      "dead_error": null
    },
    "created_at": "2023-04-28T12:34:56.789Z"
  }
  ```

  ```json Transaction Update theme={"system"}
  {
    "filters": ["transactions"],
    "transaction": {
      "transaction": {
        "signature": "BASE58_ENCODED_SIGNATURE",
        "is_vote": false,
        "transaction": {
          "signatures": ["BASE58_ENCODED_SIGNATURE"],
          "message": {
            "header": {
              "num_required_signatures": 1,
              "num_readonly_signed_accounts": 0,
              "num_readonly_unsigned_accounts": 1
            },
            "account_keys": ["BASE58_ENCODED_PUBKEY1", "BASE58_ENCODED_PUBKEY2"],
            "recent_blockhash": "BASE58_ENCODED_BLOCKHASH",
            "instructions": [
              {
                "program_id_index": 1,
                "accounts": [0],
                "data": "BASE64_ENCODED_INSTRUCTION_DATA"
              }
            ]
          }
        },
        "meta": {
          "err": null,
          "fee": 5000,
          "pre_balances": [10000000, 1],
          "post_balances": [9995000, 1],
          "pre_token_balances": [],
          "post_token_balances": [],
          "log_messages": ["Program log: Instruction executed"],
          "rewards": []
        },
        "index": 2
      },
      "slot": 189554321
    },
    "created_at": "2023-04-28T12:34:56.789Z"
  }
  ```

  ```json Block Metadata Update theme={"system"}
  {
    "filters": ["blocks_meta"],
    "block_meta": {
      "slot": 189554321,
      "blockhash": "BASE58_ENCODED_BLOCKHASH",
      "rewards": [
        {
          "pubkey": "BASE58_ENCODED_PUBKEY",
          "lamports": 1785000,
          "post_balance": 48589432109,
          "reward_type": 0,
          "commission": 10
        }
      ],
      "block_time": 1682684096,
      "block_height": 185432109,
      "parent_slot": 189554320,
      "parent_blockhash": "BASE58_ENCODED_PARENT_BLOCKHASH",
      "executed_transaction_count": 2576,
      "entries_count": 16
    },
    "created_at": "2023-04-28T12:34:56.789Z"
  }
  ```

  ```json Entry Update theme={"system"}
  {
    "filters": ["entry"],
    "entry": {
      "slot": 189554321,
      "index": 5,
      "num_hashes": 8765432,
      "hash": "BASE58_ENCODED_HASH",
      "executed_transaction_count": 128,
      "starting_transaction_index": 1024
    },
    "created_at": "2023-04-28T12:34:56.789Z"
  }
  ```

  ```json Pong Response theme={"system"}
  {
    "filters": [],
    "pong": {
      "id": 1
    },
    "created_at": "2023-04-28T12:34:56.789Z"
  }
  ```
</ResponseExample>