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

<AgentInstructions>

## Submitting Feedback

If you encounter incorrect, outdated, or confusing documentation on this page, submit feedback:

POST https://docs.chainstack.com/feedback

```json
{
  "path": "/reference/base-newfilter",
  "feedback": "Description of the issue"
}
```

Only submit feedback when you have something specific and actionable to report.

</AgentInstructions>

# eth_newFilter | Base

Base API method `eth_newFilter` creates a new filter object for monitoring log entries that match specified criteria. This method is crucial for applications that need to track events or changes in smart contracts.

The example tracks all transfers of the [USDC token](https://basescan.org/address/0x833589fcd6edb6e08f4c7c32d4f71b54bda02913).

Once you install the filter, track the changes with [eth\_getFilterChanges](/reference/getfilterchanges).

<Check>
  **Get your own node endpoint today**

  [Start for free](https://console.chainstack.com/) and get your app to production levels immediately. No credit card required.

  You can sign up with your GitHub, X, Google, or Microsoft account.
</Check>

## Parameters

* `filterObject` — an object containing filter options:
  * `fromBlock` — (optional) the block number (in hexadecimal) or one of the strings `"earliest"`, `"latest"`, or `"pending"` from where to start filtering. Default is `"latest"`.
  * `address` — (optional) an address or a list of addresses to only get logs from specific contracts.
  * `topics` — (optional) an array of topics to filter for log entries. Each event signature generated by the EVM logging mechanism has a unique topic.

## Response

* `result` — the ID of the created filter. This ID is used to identify and manage the filter with other filter methods like `eth_getFilterChanges` or `eth_getFilterLogs`.

## Use case

The `eth_newFilter` method is essential for:

* DApps that need to react to specific events emitted by smart contracts, such as token transfers or contract state changes.
* Wallets and services that provide users with notifications based on contract interactions.
* Developers and analysts monitoring specific contracts or topics for changes or patterns.


## OpenAPI

````yaml /openapi/base_node_api/eth_newFilter.json POST /2fc1de7f08c0465f6a28e3c355e0cb14
openapi: 3.0.0
info:
  title: eth_newFilter example
  version: 1.0.0
  description: >-
    This is an API example for eth_newFilter, a method to create a new filter
    object for monitoring log entries  matching the given criteria, using
    specified values.
servers:
  - url: https://base-mainnet.core.chainstack.com
security: []
paths:
  /2fc1de7f08c0465f6a28e3c355e0cb14:
    post:
      tags:
        - Ethereum Operations
      summary: eth_newFilter
      operationId: newFilter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                jsonrpc:
                  type: string
                  default: '2.0'
                method:
                  type: string
                  default: eth_newFilter
                id:
                  type: integer
                  default: 1
                params:
                  type: array
                  items:
                    type: object
                    properties:
                      fromBlock:
                        type: string
                        default: latest
                      address:
                        type: string
                        default: '0x833589fcd6edb6e08f4c7c32d4f71b54bda02913'
                      topics:
                        type: array
                        items:
                          type: string
                        default:
                          - >-
                            0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef
                  default:
                    - fromBlock: latest
                      address: '0x833589fcd6edb6e08f4c7c32d4f71b54bda02913'
                      topics:
                        - >-
                          0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef
      responses:
        '200':
          description: The ID of the created filter
          content:
            application/json:
              schema:
                type: object
                properties:
                  jsonrpc:
                    type: string
                  id:
                    type: integer
                  result:
                    type: string

````