# eth\_newFilter

Creates a filter object, based on filter options, to notify when the state changes (logs). To check if the state has changed, call [eth\_getFilterChanges](https://docs.validationcloud.io/v1/arbitrum/execution-api/eth_getfilterchanges).

This method will use `40` [Compute Units](https://docs.validationcloud.io/v1/about/billing).

***

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

**A note on specifying topic filters:** Topics are order-dependent. A transaction with a log with topics \[A, B] will be matched by the following topic filters:

* `[]` "anything"
* `[A]` "A in first position (and anything after)"
* `[null, B]` "anything in first position AND B in second position (and anything after)"
* `[A, B]` "A in first position AND B in second position (and anything after)"
* `[[A, B], [A, B]]` "(A OR B) in first position AND (A OR B) in second position (and anything after)"

## **Parameters**

`Object` - The filter options:

* `fromBlock`: `QUANTITY|TAG` - (optional, default: `"latest"`) Integer block number, or `"latest"` for the last mined block, `"safe"` for the latest safe block, `"finalized"` for the latest finalized block, or `"pending"`, `"earliest"` for not yet mined transactions.
* `toBlock`: `QUANTITY|TAG` - (optional, default: `"latest"`) Integer block number, or `"latest"` for the last mined block, `"safe"` for the latest safe block, `"finalized"` for the latest finalized block, or `"pending"`, `"earliest"` for not yet mined transactions.
* `address`: `DATA|Array`, 20 Bytes - (optional) Contract address or a list of addresses from which logs should originate.
* `topics`: `Array of DATA`, - (optional) Array of 32 Bytes `DATA` topics. Topics are order-dependent. Each topic can also be an array of DATA with "or" options.

```bash
params: [
  {
    fromBlock: "0x1",
    toBlock: "0x2",
    address: "0x8888f1f195afa192cfee860698584c030f4c9db1",
    topics: [
      "0x000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b",
      null,
      [
        "0x000000000000000000000000a94f5374fce5edbc8e2a8697c15331677e6ebf0b",
        "0x0000000000000000000000000aff3454fce5edbc8cca8697c15331677e6ebccc",
      ],
    ],
  },
]
```

## **Returns**

`QUANTITY`  - A filter id.

```bash
// Result
{
  "id":1,
  "jsonrpc": "2.0",
  "result": "0x1" // 1
}
```

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

```bash
curl https://mainnet.ethereum.validationcloud.io/v1/<YOUR_API_KEY_HERE> \
    -X POST \
    -H "Content-Type: application/json" \
    -d '{"jsonrpc":"2.0","method":"eth_newFilter","params":[{"topics":["0x12341234"]}],"id":73}'

```

{% endtab %}

{% tab title="testnet" %}

```bash
curl https://sepolia.ethereum.validationcloud.io/v1/<YOUR_API_KEY_HERE> \
    -X POST \
    -H "Content-Type: application/json" \
    -d '{"jsonrpc":"2.0","method":"eth_newFilter","params":[{"topics":["0x12341234"]}],"id":73}'

```

{% endtab %}
{% endtabs %}