> ## 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_getBlockTransactionCountByNumber | Optimism

> Optimism API method that retrieves the number of transactions in a block, identified by its number. Chainstack Optimism reference.

Optimism API method that retrieves the number of transactions in a block, identified by its number. This method allows for understanding the transaction volume within a specific block without needing to load the entire block's data.

## Parameters

* `blockNumber` — the number of the block for which the transaction count is being queried, encoded as a hexadecimal string.

## Response

* `result` — the number of transactions in the specified block, encoded as a hexadecimal string. This includes all transactions that were part of the block at the time it was mined.

## Use case

The `eth_getBlockTransactionCountByNumber` method is useful for applications that monitor blockchain activity, such as wallets, block explorers, or analytics platforms. It can help these applications quickly gauge the level of activity within specific blocks or over a range of blocks.


## OpenAPI

````yaml openapi/optimism_node_api/eth_getBlockTransactionCountByNumber.json POST /efb0a5eccd2caa5135eb54eba6f7f300
openapi: 3.0.0
info:
  title: eth_getBlockTransactionCountByNumber example
  version: 1.0.0
  description: This is an API example for eth_getBlockTransactionCountByNumber.
servers:
  - url: https://optimism-mainnet.core.chainstack.com
security: []
paths:
  /efb0a5eccd2caa5135eb54eba6f7f300:
    post:
      tags:
        - Ethereum Operations
      summary: eth_getBlockTransactionCountByNumber
      operationId: getBlockTransactionCountByNumber
      requestBody:
        required: true
        content:
          application/json:
            schema:
              type: object
              properties:
                jsonrpc:
                  type: string
                  default: '2.0'
                method:
                  type: string
                  default: eth_getBlockTransactionCountByNumber
                id:
                  type: integer
                  default: 1
                params:
                  type: array
                  items:
                    anyOf:
                      - type: string
                        default: '0x6ecf0b4'
                  default:
                    - '0x6ecf0b4'
      responses:
        '200':
          description: The transaction count of the block by number
          content:
            application/json:
              schema:
                type: object
                properties:
                  jsonrpc:
                    type: string
                  id:
                    type: integer
                  result:
                    type: string

````