⚠️Blast API (blastapi.io) ends Oct 31. Migrate to Dwellir and skip the expensive compute units.
Switch Today →
Skip to main content

author_pendingExtrinsics - JSON-RPC Method

Description​

Returns an array of all pending extrinsics currently in the transaction pool, waiting to be included in a future block. This JSON-RPC method is useful for monitoring transaction pool status and debugging transaction submission issues.

Parameters​

This method does not require any parameters.

Returns​

FieldTypeDescription
resultarrayArray of hex-encoded pending extrinsics

Request Example​

{
  "jsonrpc": "2.0",
  "method": "author_pendingExtrinsics",
  "params": [],
  "id": 1
}

Response Example​

{
  "jsonrpc": "2.0",
  "result": [
    "0x450284008eaf04151687736326c9fea17e25fc5287613693c912909cb226aa4794f26a48...",
    "0x450284d717d5031504025a62020b00000000000000e143f23803ac50e8f6f8e62695..."
  ],
  "id": 1
}

Code Examples​

cURL​

curl https://api-polkadot.n.dwellir.com \
  -X POST \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "author_pendingExtrinsics",
    "params": [],
    "id": 1
  }'

JavaScript​

const getPendingExtrinsics = async () => {
  const response = await fetch('https://api-polkadot.n.dwellir.com', {
    method: 'POST',
    headers: {
      'Authorization': 'Bearer YOUR_API_KEY',
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      jsonrpc: '2.0',
      method: 'author_pendingExtrinsics',
      params: [],
      id: 1
    })
  });
  
  const data = await response.json();
  console.log(`Found ${data.result.length} pending extrinsics`);
  return data.result;
};

Python​

import requests
import json

def get_pending_extrinsics():
    url = "https://api-polkadot.n.dwellir.com"
    headers = {
        "Authorization": "Bearer YOUR_API_KEY",
        "Content-Type": "application/json"
    }
    
    payload = {
        "jsonrpc": "2.0",
        "method": "author_pendingExtrinsics",
        "params": [],
        "id": 1
    }
    
    response = requests.post(url, headers=headers, data=json.dumps(payload))
    data = response.json()
    
    if "error" in data:
        raise Exception(f"RPC Error: {data['error']}")
    
    return data["result"]

# Monitor pending transactions
pending = get_pending_extrinsics()
print(f"Pending transactions: {len(pending)}")

Use Cases​

  1. Transaction Pool Monitoring: Check congestion levels
  2. Fee Estimation: Analyze pending transactions to determine appropriate fees
  3. Transaction Debugging: Verify if a transaction reached the pool
  4. MEV Analysis: Monitor pending transactions for arbitrage opportunities
  5. Network Health: Assess network activity and load

Notes​

  • Returns empty array if no pending extrinsics
  • Includes all types of extrinsics (transfers, staking, governance, etc.)
  • Extrinsics are hex-encoded and need decoding to inspect details
  • Pool size is limited; old or low-priority transactions may be dropped
  • Not all pending extrinsics will be included in the next block