The eth_getBlockTransactionCountByHash method returns the number of transactions in a block, identified by the block's hash. This lightweight method provides a quick way to check transaction volume without retrieving the full block data, making it useful for block explorers and network analysis tools.

Use Cases

Block explorer functionalities and transaction listings
Network activity monitoring and volume analysis
Transaction volume analysis and historical tracking
Block size estimation and gas usage prediction
Chain reorganization detection and validation
Synchronization verification between nodes
Transaction throughput measurement
Blockchain analytics and usage metrics
Block verification and validation checks
MEV (Maximal Extractable Value) research

Method Details

This method accepts a block hash and returns the number of transactions in that block, providing a simple yet efficient way to gauge block activity.

Paramètres:

hashstring[required]

The hash (32 bytes) of the block

Retours:

resultstring

The number of transactions in the specified block (hexadecimal)

Response Example

{
	"jsonrpc": "2.0",
	"id": 1,
	"result": "0x134" // 308 transactions in decimal
}

Understanding the Response

The response is a hexadecimal string representing the number of transactions in the block:

"0x0" means the block has no transactions (empty block)
"0x1" means there is only one transaction
"0x134" (as shown above) converts to 308 in decimal, indicating 308 transactions

To convert the hex response to decimal in JavaScript:

const txCount = parseInt("0x134", 16); // 308

Block Hash vs. Block Number

This method uses a block hash as an identifier, which has these characteristics:

Uniqueness: Even in case of chain reorganizations, the block hash uniquely identifies a specific block
Immutability: The block hash never changes, unlike block numbers which can be reassigned
Verifiability: The hash can be independently verified as it's derived from the block's contents

If you have a block number instead of a hash, use eth_getBlockTransactionCountByNumber instead.

Practical Example

// Example: Find blocks with high transaction counts
const significantBlockHashes = [
	'0xba9ded5ca1ec9adb9451bf053b33cbf5bd60f2a7ea39256278db165de9a88e5c', // Example high-activity block
	'0xb37a9f99b47975acc1ea43bd2e02e0567566bd3dad8f034ab676b4a94d1bac9a', // Another block to check
	'0x98c3125c2993d90b396f638115821ba17b9852e4001869061b800d32f96cdd2b', // Yet another block
];

async function findHighActivityBlocks(blockHashes, threshold = 100) {
	const results = [];

	for (const hash of blockHashes) {
		const count = await provider.send('eth_getBlockTransactionCountByHash', [hash]);
		const txCount = parseInt(count, 16);

		if (txCount > threshold) {
			results.push({
				blockHash: hash,
				transactionCount: txCount,
			});
		}
	}

	return results.sort((a, b) => b.transactionCount - a.transactionCount);
}

// Usage
const highActivityBlocks = await findHighActivityBlocks(significantBlockHashes);
console.log('Blocks with high transaction counts:', highActivityBlocks);

Historical Context

Transaction counts per block have evolved significantly throughout Ethereum's history:

Early Ethereum (2015-2016): 0-50 transactions per block
2017 ICO boom: 70-150 transactions per block
2020 DeFi summer: 150-250 transactions per block
Post-London upgrade (EIP-1559): 200-300+ transactions per block
Post-Merge (2022+): 200-400+ transactions per block depending on network demand

High transaction counts typically correlate with:

Higher gas prices due to increased demand
Network congestion during peak usage
Major market moves or significant events
Popular NFT mints or token launches
DeFi yield farming opportunities

eth_getBlockTransactionCountByHash