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The Public Mempool stream delivers low-latency pushes of every pending transaction broadcast across the BSC network. By connecting to this WebSocket endpoint, your application receives a live feed of unconfirmed transactions the moment they appear in the mempool — giving you the edge needed for backrunning, copy trading, sniping, and other latency-sensitive strategies. The stream is priced at $300 per stream per month, with volume discounts available for multi-month subscriptions.
This stream covers the public BSC mempool — all transactions propagated through the peer-to-peer network. For transactions submitted through BlockRazor RPC that are not yet public, see the Private Mempool stream.

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Connection Details

PropertyValue
ProtocolWebSocket (WSS)
Endpointwss://mempool.blockrazor.io/bsc/public?auth=YOUR_AUTH_TOKEN
Pricing$300 / stream / month
ChainBNB Smart Chain (BSC)
Replace YOUR_AUTH_TOKEN with the API token issued in your BlockRazor dashboard. Keep this token secret — it authenticates your subscription.

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Authentication

Pass your auth token as a query parameter when opening the WebSocket connection: 
wss://mempool.blockrazor.io/bsc/public?auth=YOUR_AUTH_TOKEN
No additional handshake or message is required after the connection is established. The server begins streaming pending transactions immediately upon successful authentication.

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Code Example

The example below uses the ws package for Node.js to connect and log every incoming pending transaction: 
const WebSocket = require('ws');

const ws = new WebSocket('wss://mempool.blockrazor.io/bsc/public?auth=YOUR_AUTH_TOKEN');

ws.on('open', () => console.log('Connected to Public Mempool'));

ws.on('message', (data) => {
  const tx = JSON.parse(data);
  console.log('Pending tx:', tx.hash, 'from:', tx.from);
});

ws.on('error', (err) => console.error('Error:', err));
Parse tx.gasPrice and compare it against your target thresholds to quickly filter for high-priority transactions without processing every message downstream.

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Response Fields

Each WebSocket message is a JSON object representing a single pending transaction. The fields are described below.
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hash
string
required
The transaction hash — a 32-byte hex string uniquely identifying this pending transaction on the BSC network (e.g. 0xabc123...).
​
from
string
required
The sender’s Ethereum-compatible address that signed and originated the transaction (e.g. 0xDe0B295...).
​
to
string
required
The recipient address or contract address being called. May be null for contract-creation transactions.
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value
string
required
The amount of BNB transferred, expressed as a hex-encoded integer in wei (e.g. "0x16345785d8a0000" for 0.1 BNB).
​
gas
string
required
The gas limit set by the sender, as a hex-encoded integer (e.g. "0x5208" for 21000 gas).
​
gasPrice
string
required
The gas price the sender is willing to pay, expressed as a hex-encoded integer in wei (e.g. "0x3B9ACA00" for 1 Gwei).
​
data
string
required
The ABI-encoded calldata for the transaction. Empty string ("0x") for simple BNB transfers; contains function selector and arguments for contract calls.

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Example Message

{
  "hash": "0xf4a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8a9b0c1d2e3f4a5b6c7d8e9f0a1",
  "from": "0xDe0B295669a9FD93d5F28D9Ec85E40f4cb697BA",
  "to": "0x10ED43C718714eb63d5aA57B78B54704E256024E",
  "value": "0x0",
  "gas": "0x493E0",
  "gasPrice": "0x12A05F200",
  "data": "0x38ed173900000000000000000000000000000000000000000000000000038d7ea4c68000"
}

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Pricing & Discounts

Subscription PeriodDiscount
1 month—
3 months5% off
6 months10% off
9 months15% off
12 months20% off
The Public Mempool stream is also available as part of the BSC Package bundle. See the Pricing page for details.

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