eth_getBlockTransactionCountByHash - Ethereum

Example code for the eth_getBlockTransactionCountByHash JSON RPC method. Сomplete guide on how to use eth_getBlockTransactionCountByHash JSON RPC in GetBlock Web3 documentation.

This method returns the number of transactions in a block, identified by block hash, hex-encoded. A lightweight alternative to fetching the full block when only the transaction count is needed — for example, to compute activity metrics without materializing the transaction list.

Parameters

Parameter	Type	Required	Description
blockHash	string	Yes	32-byte block hash

Request

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "eth_getBlockTransactionCountByHash",
    "params": [
        "0x9ec8e2f6b78d8f5f2ac3e5d61b0d38d4d5a8f0e7c8b5a2f9d3e6c1b7a4d0f2e5c"
    ],
    "id": "getblock.io"
}'

Axios

example.js

const axios = require('axios');

const response = await axios.post('https://go.getblock.io/<ACCESS-TOKEN>/', {
    jsonrpc: '2.0',
    method: 'eth_getBlockTransactionCountByHash',
    params: [
        "0x9ec8e2f6b78d8f5f2ac3e5d61b0d38d4d5a8f0e7c8b5a2f9d3e6c1b7a4d0f2e5c"
    ],
    id: 'getblock.io'
}, {
    headers: { 'Content-Type': 'application/json' }
});

console.log(response.data.result);

Request

example.py

import requests

response = requests.post(
    'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers={'Content-Type': 'application/json'},
    json={
        'jsonrpc': '2.0',
        'method': 'eth_getBlockTransactionCountByHash',
        'params': [
            "0x9ec8e2f6b78d8f5f2ac3e5d61b0d38d4d5a8f0e7c8b5a2f9d3e6c1b7a4d0f2e5c"
        ],
        'id': 'getblock.io'
    }
)

print(response.json())

Rust

example.rs

use reqwest::Client;
use serde_json::{json, Value};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();
    
    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&json!({
            "jsonrpc": "2.0",
            "method": "eth_getBlockTransactionCountByHash",
            "params": [
                "0x9ec8e2f6b78d8f5f2ac3e5d61b0d38d4d5a8f0e7c8b5a2f9d3e6c1b7a4d0f2e5c"
            ],
            "id": "getblock.io"
        }))
        .send()
        .await?
        .json::<Value>()
        .await?;
    
    println!("Result: {}", response["result"]);
    Ok(())
}

Response

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

Response Parameters

Parameter	Type	Description
jsonrpc	string	JSON-RPC protocol version ("2.0")
id	string	Request identifier matching the request
result	string	Hex-encoded transaction count in the block

Use Cases

• Block Activity Metrics: Cheap poll of per-block transaction count for dashboards

• Iteration Bounds: Determine the loop bound for iterating transactions by (blockHash, index)

• Reorg-Safe Activity Snapshots: Get per-block counts referenced by hash rather than number

Error Handling

Error Code	Message	Description
-32602	Invalid params	Block hash is malformed
-32603	Internal error	Node failed to look up the block

Web3 Integration

Ethers.js

ethers-example.js

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider('https://go.getblock.io/<ACCESS-TOKEN>/');

const countHex = await provider.send('eth_getBlockTransactionCountByHash', ['0x9ec8e2f6b78d8f5f2ac3e5d61b0d38d4d5a8f0e7c8b5a2f9d3e6c1b7a4d0f2e5c']);
console.log('Transaction count:', parseInt(countHex, 16));

Viem

viem-example.js

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

const client = createPublicClient({
    chain: mainnet,
    transport: http('https://go.getblock.io/<ACCESS-TOKEN>/'),
});

const count = await client.getBlockTransactionCount({ blockHash: '0x9ec8e2f6b78d8f5f2ac3e5d61b0d38d4d5a8f0e7c8b5a2f9d3e6c1b7a4d0f2e5c' });
console.log('Transaction count:', count);