Google reCAPTCHA Node.js tutorial

As of my last knowledge update in January 2022, I can provide you with a general guideline on how to integrate Google reCAPTCHA with Node.js. Keep in mind that the details may have changed, so it's always a good idea to refer to the official documentation for the most up-to-date information.

Here's a step-by-step guide on how you might integrate Google reCAPTCHA with a Node.js application:

  1. Get reCAPTCHA API Key:
    • Visit the reCAPTCHA website and sign in with your Google account.
    • Click on the "+" icon to create a new site.
    • Choose the type of reCAPTCHA (v2 "I'm not a robot" Checkbox or v3) and fill in the required information.
    • Accept the reCAPTCHA Terms of Service and click on the "Submit" button.
    • After submission, you will be provided with the "Site Key" and "Secret Key." Keep these keys secure.
  2. Set Up Node.js Project:
    • Create a new Node.js project if you haven't already:

                        mkdir your-project-name
                        cd your-project-name
                        npm init -y                    

  3. Install Dependencies:
    • Install the necessary packages using npm:

                        npm install express body-parser axios

  4. Create an Express Server:
    • Create a simple Express server in your index.js or app.js file:

                        const express = require('express');
                        const bodyParser = require('body-parser');
                        const axios = require('axios');
                        const app = express();
                        const port = 3000;
                        app.use(bodyParser.urlencoded({ extended: true }));
                        app.use(express.static('public')); // Assuming your HTML file is in a 'public' directory
                        app.get('/', (req, res) => {
                          res.sendFile(__dirname + '/public/index.html');
              '/submit', async (req, res) => {
                          const { grecaptchaResponse } = req.body;
                          // Verify reCAPTCHA token
                          const secretKey = 'YOUR_SECRET_KEY'; // Replace with your secret key
                          const verificationURL = `${secretKey}&response=${grecaptchaResponse}`;
                          try {
                            const recaptchaResponse = await;
                            const { success } =;
                            if (success) {
                              // Handle successful verification
                            } else {
                              // Handle failed verification
                              res.send('Failed verification. Please try again.');
                          } catch (error) {
                            console.error('Error verifying reCAPTCHA:', error);
                            res.status(500).send('Internal Server Error');
                        app.listen(port, () => {
                          console.log(`Server is running at http://localhost:${port}`);

  5. Create HTML Form:
    • Create an HTML file in the 'public' directory (or a directory specified in your server code) with a form that includes the reCAPTCHA widget:

                     <!-- public/index.html -->
                    <!DOCTYPE html>
                    <html lang="en">
                               <meta charset="UTF-8">
                               <meta name="viewport" content="width=device-width, initial-scale=1.0">
                               <title>reCAPTCHA Example</title>
                               <script src="" async defer></script>
                             <h1>reCAPTCHA Example</h1>
                        <form action="/submit" method="post">
                            <!-- Your other form fields go here -->
                            <div class="g-recaptcha" data-sitekey="YOUR_SITE_KEY"></div>
                            <button type="submit">Submit</button>

    Replace YOUR_SECRET_KEY and YOUR_SITE_KEY with the actual keys you obtained from the reCAPTCHA website.

  6. Run Your Application:
    • Start your Node.js application:

                        node index.js

This is a basic example, and you might need to adjust it based on the specific requirements of your application. Make sure to check the latest reCAPTCHA documentation for any updates or changes.

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