> For the complete documentation index, see [llms.txt](https://docs.chainrpc.io/chainrpc/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.chainrpc.io/chainrpc/networks/ethereum/json-rpc-methods/filter-methods/eth_newfilter.md).

# 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](/chainrpc/networks/ethereum/json-rpc-methods/filter-methods/eth_getfilterchanges.md)

#### REQUEST PAYLOAD

* `FILTER OBJECT`
  * `address` *\[optional]* - a contract address or a list of addresses from which logs should originate.
  * `fromBlock` *\[optional, default is "latest"]* - hexadecimal block number, or the string "latest", "earliest" or "pending"
  * `toBlock` *\[optional, default is "latest"]* - hexadecimal block number, or the string "latest", "earliest" or "pending"
  * `topics`*\[optional]* - Array of 32 Bytes DATA topics. Topics are order-dependent.

**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)

Filter IDs will be valid for up to fifteen minutes, and can polled by any connection using the same v3 project ID.

#### EXAMPLE

```bash
## JSON-RPC over HTTPS POST
## Replace YOUR-API-KEY with an API key from your chainRPC Dashboard
## You can also replace mainnet with a different supported network
curl https://eth.chainrpc.io/v3/YOUR-API-KEY \
    -X POST \
    -H "Content-Type: application/json" \
    -d '{"jsonrpc":"2.0","method":"eth_newFilter","params":[{"topics": ["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"]}],"id":1}'

## JSON-RPC over WSS
## Replace YOUR-API-KEY with an API key from your chainRPC Dashboard
## You can also replace mainnet with a different supported network
wscat -c wss://eth.chainrpc.io/v3/YOUR-API-KEY
>{"jsonrpc":"2.0","method":"eth_newFilter","params":[{"topics": ["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"]}],"id":1}
```

### RESPONSE

#### RESULT FIELDS

* `FILTER ID` - A string denoting the newly created filter id

#### BODY

```json
{
    "jsonrpc":"2.0",
    "id":1,
    "result":"0x10ff0bfba9472c87932c56632eef8f5cc70910e8e71d"
}
```