Fast Mode: Accelerated Transaction Submission

BlockRazor’s Fast mode is purpose-built for applications where latency is the difference between a successful trade and a missed opportunity. It routes your transactions through a globally distributed acceleration network, delivering them simultaneously to highly staked validators for rapid on-chain inclusion. Rather than paying gas through the standard fee market, Fast mode embeds the tip directly inside the transaction itself — forwarded to a designated address — giving validators a direct incentive to prioritize your transaction.

How Fast Mode Works

Build your transaction

Construct a standard signed transaction for your target chain, embedding the tip payment to BlockRazor’s designated tip address inside the transaction body.

Submit to BlockRazor's Fast endpoint

Send the signed transaction to the BlockRazor Fast API. Your request is instantly fanned out across BlockRazor’s globally distributed relay nodes.

Validator delivery & block inclusion

BlockRazor forwards the transaction to a network of highly staked validators simultaneously. The embedded tip incentivizes validators to include your transaction in the next available block.

In Fast mode, the tip is not paid as a separate EIP-1559 priority fee — it must be embedded within the transaction itself as a transfer to BlockRazor’s designated tip address. Refer to the API reference for each chain’s tip address.

Supported Chains & Rate Limits

Solana

Send Transaction and Send Transaction v2. Default limit for new users: 3 TPS.

BSC

eth_sendRawTransaction and eth_sendRawTransaction v2. Default limit for new users: 10 TPS.

Base

eth_sendRawTransaction. Default limit for new users: 10 TPS.

Sui

ExecuteTransactionBlock. Contact BlockRazor for limit details.

Monad

Standard transaction submission via the Fast acceleration network. Coming soon.

New registered users can also use SendTx — a tip-free variant of Fast mode — with a limit of 10 transactions per 5 seconds and 10 transactions per day. This is a great way to evaluate the service before subscribing. The full Fast-Tx plan for BSC is $500/month.

Sending a Fast Transaction

BSC
Solana
Base
Sui

On BSC, Fast mode uses the standard eth_sendRawTransaction JSON-RPC method. The tip must be included as a value transfer to BlockRazor’s designated BSC tip address within the same transaction or as a separate transaction in the batch.

cURL

curl -X POST https://fast.blockrazor.io/bsc \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer YOUR_AUTH_TOKEN' \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_sendRawTransaction",
    "params": ["0xSIGNED_TX_HEX_WITH_TIP"],
    "id": 1
  }'

ethers.js

import { ethers } from "ethers";

// Connect to BlockRazor Fast endpoint for BSC
const provider = new ethers.JsonRpcProvider(
  "https://fast.blockrazor.io/bsc?auth=YOUR_AUTH_TOKEN"
);

const wallet = new ethers.Wallet("YOUR_PRIVATE_KEY", provider);

// The tip transfer to BlockRazor's designated address must be
// embedded within the transaction itself.
const tx = await wallet.sendTransaction({
  to: "0xBLOCKRAZOR_TIP_ADDRESS",
  value: ethers.parseEther("0.001"), // tip amount
});

console.log("Fast transaction submitted:", tx.hash);
await tx.wait();
console.log("Transaction confirmed in block:", tx.blockNumber);

Batch Submission (v2)

import { ethers } from "ethers";

const provider = new ethers.JsonRpcProvider(
  "https://fast.blockrazor.io/bsc?auth=YOUR_AUTH_TOKEN"
);

// eth_sendRawTransaction v2 accepts an array of signed transactions
const signedTxs = ["0xSIGNED_TX_1", "0xSIGNED_TX_2"];

const result = await provider.send("eth_sendRawTransaction", signedTxs);
console.log("Batch submitted:", result);

On Solana, Fast mode accepts standard base-64 encoded signed transactions. The tip is embedded as a SOL transfer to BlockRazor’s Solana tip account within the transaction instructions.

cURL

curl -X POST https://fast.blockrazor.io/solana \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer YOUR_AUTH_TOKEN' \
  -d '{
    "jsonrpc": "2.0",
    "method": "sendTransaction",
    "params": [
      "BASE64_ENCODED_SIGNED_TRANSACTION",
      {
        "encoding": "base64",
        "skipPreflight": true,
        "maxRetries": 0
      }
    ],
    "id": 1
  }'

JavaScript (@solana/web3.js)

import {
  Connection,
  Keypair,
  SystemProgram,
  Transaction,
  sendAndConfirmTransaction,
  LAMPORTS_PER_SOL,
  PublicKey,
} from "@solana/web3.js";

const connection = new Connection(
  "https://fast.blockrazor.io/solana?auth=YOUR_AUTH_TOKEN",
  "confirmed"
);

const payer = Keypair.fromSecretKey(YOUR_SECRET_KEY);
const blockrazorTipAccount = new PublicKey("BLOCKRAZOR_SOLANA_TIP_ADDRESS");

const transaction = new Transaction();

// Your primary instruction
transaction.add(
  SystemProgram.transfer({
    fromPubkey: payer.publicKey,
    toPubkey: new PublicKey("RECIPIENT_ADDRESS"),
    lamports: 0.01 * LAMPORTS_PER_SOL,
  })
);

// Embed the tip to BlockRazor's tip account
transaction.add(
  SystemProgram.transfer({
    fromPubkey: payer.publicKey,
    toPubkey: blockrazorTipAccount,
    lamports: 1000, // tip in lamports
  })
);

const signature = await sendAndConfirmTransaction(connection, transaction, [
  payer,
]);
console.log("Fast Solana transaction confirmed:", signature);

On Base, Fast mode uses eth_sendRawTransaction with the tip embedded in the transaction value.

cURL

curl -X POST https://fast.blockrazor.io/base \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer YOUR_AUTH_TOKEN' \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_sendRawTransaction",
    "params": ["0xSIGNED_TX_HEX_WITH_TIP"],
    "id": 1
  }'

ethers.js

import { ethers } from "ethers";

const provider = new ethers.JsonRpcProvider(
  "https://fast.blockrazor.io/base?auth=YOUR_AUTH_TOKEN"
);

const wallet = new ethers.Wallet("YOUR_PRIVATE_KEY", provider);

const tx = await wallet.sendTransaction({
  to: "0xBLOCKRAZOR_BASE_TIP_ADDRESS",
  value: ethers.parseEther("0.0005"),
});

console.log("Fast Base transaction submitted:", tx.hash);
await tx.wait();

Base Fast mode has a default limit of 10 TPS for new registered users. Subscribe to the Fast-Tx plan to remove this limit.

On Sui, Fast mode wraps the standard sui_executeTransactionBlock method and routes it through BlockRazor’s acceleration network.

cURL

curl -X POST https://fast.blockrazor.io/sui \
  -H 'Content-Type: application/json' \
  -H 'Authorization: Bearer YOUR_AUTH_TOKEN' \
  -d '{
    "jsonrpc": "2.0",
    "method": "sui_executeTransactionBlock",
    "params": [
      "BASE64_TX_BYTES",
      ["BASE64_SIGNATURE"],
      {
        "showInput": true,
        "showEffects": true,
        "showEvents": true
      },
      "WaitForLocalExecution"
    ],
    "id": 1
  }'

API Reference

Solana Send Transaction

Full parameter reference for Solana Fast submission.

BSC eth_sendRawTransaction

Full parameter reference for BSC Fast submission.

Sui ExecuteTransactionBlock

Full parameter reference for Sui Fast submission.

Get Started

Use Cases

Transaction Submission

Streams

Block Builder

Fast Mode: Accelerated Transaction Submission

How Fast Mode Works

Supported Chains & Rate Limits

Solana

BSC

Base

Sui

Monad

Sending a Fast Transaction

cURL

ethers.js

Batch Submission (v2)

cURL

JavaScript (@solana/web3.js)

cURL

ethers.js

cURL

API Reference

Solana Send Transaction

BSC eth_sendRawTransaction

Sui ExecuteTransactionBlock

Build docs developers (and LLMs) love

Get Started

Use Cases

Transaction Submission

Streams

Block Builder

Documentation Index

​How Fast Mode Works

​Supported Chains & Rate Limits

Solana

BSC

Base

Sui

Monad

​Sending a Fast Transaction

​cURL

​ethers.js

​Batch Submission (v2)

​cURL

​JavaScript (@solana/web3.js)

​cURL

​ethers.js

​cURL

​API Reference

Solana Send Transaction

BSC eth_sendRawTransaction

Sui ExecuteTransactionBlock

Build docs developers (and LLMs) love

How Fast Mode Works

Supported Chains & Rate Limits

Sending a Fast Transaction

cURL

ethers.js

Batch Submission (v2)

cURL

JavaScript (@solana/web3.js)

cURL

ethers.js

cURL

API Reference