> ## 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.

# eth_newBlockFilter | Optimism

> Optimism API method eth_newBlockFilter creates a new filter object that notifies subscribers when a new block is added to the blockchain.

Optimism API method `eth_newBlockFilter` creates a new filter object that notifies subscribers when a new block is added to the blockchain. This method is particularly useful for applications that need to stay updated with the latest blocks for processing or monitoring purposes.

## Parameters

* `none` — This method does not require any parameters.

## Response

* `result` — the ID of the created filter. This ID is used to identify the filter in subsequent calls to methods like `eth_getFilterChanges` or `eth_getFilterLogs` to retrieve updates about new blocks.

## Use case

The `eth_newBlockFilter` method is essential for:

* Applications that perform actions triggered by the addition of new blocks, such as updating a user interface with the latest transactions or block information.
* Services that monitor the blockchain for security or analytical purposes, needing real-time data on block additions.
* Wallets and exchanges that track new blocks to confirm transactions.


## OpenAPI

````yaml openapi/optimism_node_api/eth_newBlockFilter.json POST /efb0a5eccd2caa5135eb54eba6f7f300
openapi: 3.0.0
info:
  title: eth_newBlockFilter example
  version: 1.0.0
  description: >-
    This is an API example for eth_newBlockFilter, a method to create a new
    filter object that notifies when a  new block is added to the blockchain.
servers:
  - url: https://optimism-mainnet.core.chainstack.com
security: []
paths:
  /efb0a5eccd2caa5135eb54eba6f7f300:
    post:
      tags:
        - Ethereum Operations
      summary: eth_newBlockFilter
      operationId: newBlockFilter
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                jsonrpc:
                  type: string
                  default: '2.0'
                method:
                  type: string
                  default: eth_newBlockFilter
                id:
                  type: integer
                  default: 1
      responses:
        '200':
          description: The ID of the created block filter
          content:
            application/json:
              schema:
                type: object
                properties:
                  jsonrpc:
                    type: string
                  id:
                    type: integer
                  result:
                    type: string

````