JS

This page describes how to build and send Solana transactions using JS

Solana's transaction sending service is no longer bound to the subscription plan. API key could be required from Authentication. If you need to increase the TPS limit, please contact us and we will handle it as soon as possible.

HTTP

JS

const axios = require('axios');
const web3 = require('@solana/web3.js');
const bs58 = require('bs58');

// ------------------ Configuration Constants ------------------
// BlockRazor relay endpoint address
const httpEndpoint = "http://frankfurt.solana.blockrazor.xyz:443/sendTransaction";
const healthEndpoint = "http://frankfurt.solana.blockrazor.xyz:443/health";
// Replace with your Solana RPC endpoint
const mainNetRPC = "";
// Replace with your authKey
const authKey = "";
// Replace with your private key (base58)
const privateKey = "";
// Replace with your target public key
const publicKey = "";
// Send mode
const mode = "fast";
// Safe window
const safeWindow = 5; // only take effect in sandwichMitigation mod
// Revert protection
const revertProtection = false;
// Transaction amount
const amount = 200_000;
// Tip amount
const tipAmount = 1000000;

const tipAccounts = [
    "Gywj98ophM7GmkDdaWs4isqZnDdFCW7B46TXmKfvyqSm",
    "FjmZZrFvhnqqb9ThCuMVnENaM3JGVuGWNyCAxRJcFpg9",
    "6No2i3aawzHsjtThw81iq1EXPJN6rh8eSJCLaYZfKDTG",
    "A9cWowVAiHe9pJfKAj3TJiN9VpbzMUq6E4kEvf5mUT22",
    "68Pwb4jS7eZATjDfhmTXgRJjCiZmw1L7Huy4HNpnxJ3o",
    "4ABhJh5rZPjv63RBJBuyWzBK3g9gWMUQdTZP2kiW31V9",
    "B2M4NG5eyZp5SBQrSdtemzk5TqVuaWGQnowGaCBt8GyM",
    "5jA59cXMKQqZAVdtopv8q3yyw9SYfiE3vUCbt7p8MfVf",
    "5YktoWygr1Bp9wiS1xtMtUki1PeYuuzuCF98tqwYxf61",
    "295Avbam4qGShBYK7E9H5Ldew4B3WyJGmgmXfiWdeeyV",
    "EDi4rSy2LZgKJX74mbLTFk4mxoTgT6F7HxxzG2HBAFyK",
    "BnGKHAC386n4Qmv9xtpBVbRaUTKixjBe3oagkPFKtoy6",
    "Dd7K2Fp7AtoN8xCghKDRmyqr5U169t48Tw5fEd3wT9mq",
    "AP6qExwrbRgBAVaehg4b5xHENX815sMabtBzUzVB4v8S",
];

// ------------------ Axios HTTP Client (Connection Reuse Enabled) ------------------
const httpClient = axios.create({
    timeout: 10000,
    headers: {
        'Content-Type': 'application/json',
        'apikey': authKey,
    },
    httpAgent: new (require('http').Agent)({ keepAlive: true }),
    httpsAgent: new (require('https').Agent)({ keepAlive: true }),
});

// ------------------ Periodic Health Ping to Keep Connection Alive ------------------
async function pingHealth() {
    try {
        const res = await httpClient.get(healthEndpoint);
        console.log(`Health result:`, res.data);
    } catch (err) {
        console.error('Health check failed:', err.message);
    }
}

// ------------------ Build and Send Transaction ------------------
async function sendTx() {
    const senderPrivateKey = new Uint8Array(bs58.decode(privateKey));
    const senderKeypair = web3.Keypair.fromSecretKey(senderPrivateKey);
    const receiver = new web3.PublicKey(publicKey);
    const tipAccount = new web3.PublicKey(tipAccounts[Math.floor(Math.random() * tipAccounts.length)]);

    const connection = new web3.Connection(mainNetRPC);
    const { blockhash } = await connection.getLatestBlockhash('finalized');

    const tx = new web3.Transaction()
        .add(web3.SystemProgram.transfer({
            fromPubkey: senderKeypair.publicKey,
            toPubkey: tipAccount,
            lamports: tipAmount,
        }))
        .add(web3.SystemProgram.transfer({
            fromPubkey: senderKeypair.publicKey,
            toPubkey: receiver,
            lamports: amount,
        }));

    tx.recentBlockhash = blockhash;
    tx.feePayer = senderKeypair.publicKey;
    tx.sign(senderKeypair);

    const serialized = tx.serialize();
    const base64Tx = serialized.toString('base64');

    const payload = {
        transaction: base64Tx,
        mode: mode,
        safeWindow: safeWindow,
		RevertProtection: revertProtection,
    };

    try {
        const res = await httpClient.post(httpEndpoint, payload);
        console.log('[send tx] response:', res.data);
    } catch (err) {
        console.error('SendTx failed:', err.response?.data || err.message);
    }
}

// ------------------ Main Entry ------------------
(async () => {
    // Initial health check (establish connection)
    await pingHealth();

    // Periodically send /health to keep connection alive
    setInterval(pingHealth, 30 * 1000);
    sendTx().catch(console.error);
})();

curl

Response Example

Success

{"signature":"2DkHpsZxwbGDHkCujRMqd1jXMPaXfzn2JpwxZ43PoTk6Cj7hpxDp8VHESNCeuh95nVMmsWV4RGGWCkmGERZCTWHL","error":""}

Error

{"signature":"","error":"error: Authentication information is missing. Please provide a valid auth token"}

gRPC

fast mode sandwichMitigation mode

const web3 = require("@solana/web3.js");
const bs58 = require("bs58");

const grpc = require('@grpc/grpc-js');
const protoLoader = require('@grpc/proto-loader');

const PROTO_PATH = __dirname + '/server.proto';
const packageDefinition = protoLoader.loadSync(
    PROTO_PATH,
    {
        keepCase: true,
        longs: String,
        enums: String,
        defaults: true,
        oneofs: true
    }
);

const serverProto = grpc.loadPackageDefinition(packageDefinition).serverpb;

// BlockRazor relay endpoint address
const blzRelayEndpoint = "frankfurt.solana-grpc.blockrazor.xyz:80";
// replace your solana rpc endpoint
const mainNetRPC = "";
// replace your authKey
const authKey = "";
// relace your private key(base58)
const privateKey = "";
// send mode
const mode = "fast"; // set to "sandwichMitigation" to mitigate sandwich attacks on tx
// safeWindow
const safeWindow = 3; // only take effect in sandwichMitigation mode
// Revert protection
const revertProtection = false;
// tip amount
const tipAmount = 1000000;

const tipAccounts = [
    "Gywj98ophM7GmkDdaWs4isqZnDdFCW7B46TXmKfvyqSm",
    "FjmZZrFvhnqqb9ThCuMVnENaM3JGVuGWNyCAxRJcFpg9",
    "6No2i3aawzHsjtThw81iq1EXPJN6rh8eSJCLaYZfKDTG",
    "A9cWowVAiHe9pJfKAj3TJiN9VpbzMUq6E4kEvf5mUT22",
    "68Pwb4jS7eZATjDfhmTXgRJjCiZmw1L7Huy4HNpnxJ3o",
    "4ABhJh5rZPjv63RBJBuyWzBK3g9gWMUQdTZP2kiW31V9",
    "B2M4NG5eyZp5SBQrSdtemzk5TqVuaWGQnowGaCBt8GyM",
    "5jA59cXMKQqZAVdtopv8q3yyw9SYfiE3vUCbt7p8MfVf",
    "5YktoWygr1Bp9wiS1xtMtUki1PeYuuzuCF98tqwYxf61",
    "295Avbam4qGShBYK7E9H5Ldew4B3WyJGmgmXfiWdeeyV",
    "EDi4rSy2LZgKJX74mbLTFk4mxoTgT6F7HxxzG2HBAFyK",
    "BnGKHAC386n4Qmv9xtpBVbRaUTKixjBe3oagkPFKtoy6",
    "Dd7K2Fp7AtoN8xCghKDRmyqr5U169t48Tw5fEd3wT9mq",
    "AP6qExwrbRgBAVaehg4b5xHENX815sMabtBzUzVB4v8S",
];

const client = new serverProto.Server(
    blzRelayEndpoint,
    grpc.credentials.createInsecure()
);

var meta = new grpc.Metadata();

function getRandomAccount() {
    const randomIndex = Math.floor(Math.random() * tipAccounts.length);
    return tipAccounts[randomIndex];
}

// ------------------ Periodic Health Ping to Keep Connection Alive ------------------
async function pingHealth() {
    client.getHealth({}, meta, (err, response) => {
        if (err) {
            console.error('[get health] error:', err);
            return;
        }

        console.log('[get health] response:', response);
    });
}

(async () => {
    meta.add('apikey', authKey);

    // Initial health check (establish connection)
    await pingHealth();

    // Periodically send /health to keep connection alive
    setInterval(pingHealth, 30 * 1000);

    const senderPrivateKey = new Uint8Array(bs58.decode(privateKey));
    const senderKeypair = web3.Keypair.fromSecretKey(senderPrivateKey);

    const tipAccount = getRandomAccount();
    const recipientPublicKey = new web3.PublicKey(tipAccount);

    const transaction = new web3.Transaction().add(
        web3.SystemProgram.transfer({
            fromPubkey: senderKeypair.publicKey,
            toPubkey: recipientPublicKey,
            lamports: tipAmount,
        })
    );

    const connection = new web3.Connection(mainNetRPC);

    transaction.recentBlockhash = (await connection.getLatestBlockhash()).blockhash;
    transaction.feePayer = senderKeypair.publicKey;
    transaction.sign(senderKeypair);

    const serializedTransaction = transaction.serialize();
    const base64Tx = serializedTransaction.toString('base64');

    client.SendTransaction({ transaction: base64Tx, mode: mode, safeWindow: safeWindow, revertProtection: revertProtection}, meta, (err, response) => {
        if (err) {
            console.error('[send tx] error:', err);
            return;
        }

        console.log('[send tx] response:', response);
    });
})();

Proto

syntax = "proto3";

package serverpb;

option go_package = "./pb/serverpb";


service Server {
    rpc SendTransaction(SendRequest) returns(SendResponse) {};

    rpc GetHealth(HealthRequest) returns(HealthResponse) {};
}

message SendRequest {
    string transaction = 1;
    string mode = 2;
    int32 safeWindow = 3; // only take effect in sandwichMitigation mode
    bool revertProtection = 4;
}

message SendResponse {
    string signature = 1;
}

message HealthRequest {
}

message HealthResponse {
    string status = 1;
}

Response Example

Success

[send tx] response: {signature: '3WbpmLkpgKC13XTFZDUCvjvC3uo5KincG3DTEgjWerQi1B1Frf4zwkDsEtnxBVqW3EgD1b38YWsTKAyFonRR6xSM'}

Error

[send tx] error: Error: 2 UNKNOWN: Insufficient tip, please increase the tip amount and try again, at least 1000000 lamports