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

# eth_newBlockFilter

Creates a filter in the node, to notify when a new block arrives. To check if the state has changed, call [eth\_getFilterChanges](/nodeapi/mezo/execution-api/eth_getfilterchanges).

This method will use `40` [Compute Units](/nodeapi/about/billing).

***

## Reference: [Here](https://ethereum.org/en/developers/docs/apis/json-rpc/#eth_newblockfilter)

## **Parameters**

`None`

## Returns

`QUANTITY` - A filter id.

```json theme={"theme":{"light":"github-light","dark":"github-dark-default"}}
// Result
{
  "id":1,
  "jsonrpc": "2.0",
  "result": "0x1" // 1
}
```

<CodeGroup>
  ```bash title="mainnet" theme={"theme":{"light":"github-light","dark":"github-dark-default"}}
  curl https://mainnet.mezo.validationcloud.io/v1/<YOUR_API_KEY_HERE> \
      -X POST \
      -H "Content-Type: application/json" \
      -d '{"jsonrpc":"2.0","method":"eth_newBlockFilter","params":[],"id":73}'
  ```

  ```bash title="testnet" theme={"theme":{"light":"github-light","dark":"github-dark-default"}}
  curl https://testnet.mezo.validationcloud.io/v1/<YOUR_API_KEY_HERE> \
      -X POST \
      -H "Content-Type: application/json" \
      -d '{"jsonrpc":"2.0","method":"eth_newBlockFilter","params":[],"id":73}'
  ```
</CodeGroup>


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