eth_getBlockTransactionCountByHash - Optimism

Example code for the eth_getBlockTransactionCountByHash json-rpc method. Сomplete guide on how to use eth_getBlockTransactionCountByHash json-rpc in GetBlock.io Web3 documentation.

This method retrieves the number of transactions in a block using its hash. It's useful for quickly determining block activity without fetching the full block data. On Optimism, blocks typically contain fewer transactions than Ethereum L1 due to the faster block time (~2 seconds).

Parameters

Parameter	Type	Description	Required
blockHash	DATA, 32 Bytes	The hash of a block.	Yes

Request Sample

curl

{"jsonrpc": "2.0",
"method": "eth_getBlockTransactionCountByHash",
"params": ["0xe8f38578b756a9fd05ca05dcbe56fd57ce72e9fb06a90e5064562baccf7c7a6e"], 
"id": "getblock.io"
}

Javascript(Axios)

import axios from 'axios'
let data = JSON.stringify({
    "jsonrpc": "2.0",
   "method": "eth_getBlockTransactionCountByHash",
    "params": [
        "0xe8f38578b756a9fd05ca05dcbe56fd57ce72e9fb06a90e5064562baccf7c7a6e"
    ],
    "id": "getblock.io"
};

let config = {
  method: "post",
  maxBodyLength: Infinity,
  url: "https://shared.us-east-1.getblock.io/<ACCESS_TOKEN>",
  headers: {
    "Content-Type": "application/json",
  },
  data: data,
};

axios
  .request(config)
  .then((response) => {
    console.log(JSON.stringify(response.data));
  })
  .catch((error) => {
    console.log(error);
  });

Python(Request)

import requests
import json

url = "https://shared.us-east-1.getblock.io/<ACESS_TOKEN>"

payload = json.dumps({
   "jsonrpc": "2.0",
    "method": "eth_getBlockTransactionCountByHash",
    "params": [
        "0xe8f38578b756a9fd05ca05dcbe56fd57ce72e9fb06a90e5064562baccf7c7a6e"
    ],
    "id": "getblock.io"
})
headers = {
  'Content-Type': 'application/json'
}

response = requests.request("POST", url, headers=headers, data=payload)

print(response.text)

Rust

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = reqwest::Client::builder()
        .build()?;

    let mut headers = reqwest::header::HeaderMap::new();
    headers.insert("Content-Type", "application/json".parse()?);

    let data = r#"{
   "jsonrpc": "2.0",
   "method": "eth_getBlockTransactionCountByHash",
    "params": [
        "0xe8f38578b756a9fd05ca05dcbe56fd57ce72e9fb06a90e5064562baccf7c7a6e"
    ],
    "id": "getblock.io"
}"#;

    let json: serde_json::Value = serde_json::from_str(&data)?;

    let request = client.request(reqwest::Method::POST, "https://shared.us-east-1.getblock.io/<ACCESS_TOKEN>")
        .headers(headers)
        .json(&json);

    let response = request.send().await?;
    let body = response.text().await?;

    println!("{}", body);

    Ok(())
}

Response

A successful response returns the following:

{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": "0x28"
}

Response Parameters

• id: A unique request identifier, matching the id sent in the request body.

• jsonrpc: Specifies the use of JSON-RPC version 2.0.

• result: The number of transactions in the block as a hexadecimal string.

Use Case

The eth_getBlockTransactionCountByHash method is commonly used for:

• Block analysis

• Transaction throughput monitoring

• Network activity tracking

Error handling

Status Code	Error Message	Cause
404	Not Found	Missing or invalid ACCESS_TOKEN.
-32602	Invalid argument	The block hash isn't accurate or incomplete

Integration with Web3

The eth_getBlockTransactionCountByHash can help developers:

• Power block explorers that show transaction counts without loading full blocks

• Measure chain activity for dashboards and metrics

• Build fast monitoring tools that track throughput

• Reduce bandwidth usage by avoiding heavy block queries

• Support systems that decide whether to fetch full block data based on count

Ethers.js

import { ethers } from "ethers";
const RPC_URL = "https://shared.us-east-1.getblock.io/<ACCESS_TOKEN>";
const provider = new ethers.JsonRpcProvider(RPC_URL);
async function Call() {
  try {
     const result = await provider.send("eth_getBlockTransactionCountByHash",
["0xe8f38578b756a9fd05ca05dcbe56fd57ce72e9fb06a90e5064562baccf7c7a6e"]);    
console.log("The result:", result);
    return result;
  } catch (error) {
    console.error("The error:", error);
    throw error;
  }
}

Viem

import { createPublicClient, http } from 'viem';
import { optimism } from 'viem/chains';

// Create Viem client with GetBlock
const client = createPublicClient({
  chain: optimism,
  transport: http('https://shared.us-east-1.getblock.io/<ACCESS_TOKEN>'),
});

// Using the method through Viem
async function Call() {
    try {
        // Method-specific Viem implementation
        const result = await client.request({
           method:   "eth_getBlockTransactionCountByHash",
           params:   ["0xe8f38578b756a9fd05ca05dcbe56fd57ce72e9fb06a90e5064562baccf7c7a6e"]
        });
        console.log('Result:', result);
        return result;
    } catch (error) {
        console.error('Viem Error:', error);
        throw error;
    }
}