> For the complete documentation index, see [llms.txt](https://docs.validationcloud.io/v1/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.validationcloud.io/v1/solana/websocket-unstable-methods/blocksubscribe.md).

# blockSubscribe

Subscribe to receive a notification anytime a new block is Confirmed or Finalized.

This method will use `20` [Compute Units](/v1/about/billing.md).

***

## **Parameters**

* `filters` string. The filter criteria for the logs to receive results by account type. Currently it supports the following params:
  * `all` string. Includes all transactions in a block.
  * `object` object. An object with the following field:
    * `mentionsAccountOrProgram` string Only retrieve transactions that reference the specified public key as a base-58 encoded string. If a block contains no such references, no notifications will be generated.
  * `object` *optional.* Configuration object containing the following fields:
    * `commitment` string. The level of commitment required for the query. The options include:
      * `finalized` string. The node will query the most recent block confirmed by the supermajority of the cluster as having reached maximum lockout, meaning the cluster has recognized this block as finalized.
      * `confirmed` string. The node will query the most recent block that has been voted on by the supermajority of the cluster.
      * `processed` string. The node will query its most recent block. Note that the block may not be complete.
    * `transactionDetails` string. The level of transaction detail to return, either 'full', 'signatures', or 'none'.
    * `showRewards` boolean. Indicated whether to populate the 'rewards' array.
    * `encoding` string. The encoding format for account data. It can be one of base58 (slow), base64, base64+zstd or jsonParsed.

## Returns

`result` integer The subscription id.

`blockNotification` object. The notification object with the following fields:

* `slot` integer. The corresponding slot.
* `err` object. Error if something went wrong publishing the notification otherwise null.
* `block` object. A block object as seen in the getBlock RPC HTTP method.

```bash
// Result
{
  "jsonrpc": "2.0",
  "id": "1",
  "method": "blockSubscribe",
  "params": [
    {
      "mentionsAccountOrProgram": "LieKvPRE8XeX3Y2xVNHjKlpAScD12lYySBVQ4HqoJ5op"
    },
    {
      "commitment": "confirmed",
      "encoding": "base64",
      "showRewards": true,
      "transactionDetails": "full"
    }
  ]
}
```

{% tabs %}
{% tab title="mainnet" %}

<pre class="language-bash"><code class="lang-bash"><strong>wscat -c wss://mainnet.solana.validationcloud.io/v1/&#x3C;YOUR_API_KEY_HERE>
</strong># wait for connection
{"id":1,"jsonrpc":"2.0","method":"blockSubscribe","params":["all"]}
    
</code></pre>

{% endtab %}

{% tab title="devnet" %}

```bash
wscat -c wss://devnet.solana.validationcloud.io/v1/<YOUR_API_KEY_HERE>
# wait for connection
{"id":1,"jsonrpc":"2.0","method":"accountSubscribe","params":["E645TckHQnDcavVv92Etc6xSWQaq8zzPtPRGBheviRAk",{"encoding": "jsonParsed", "commitment": "finalized"}]}
    
```

{% endtab %}
{% endtabs %}


---

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