Repost of https://dev.to/rhuzaifa/add-google-recaptcha-v2-to-plain-html-3n0p

What is it?

A CAPTCHA is a test that helps to tell the difference between a bot and a human.

The reCAPTCHA is Google’s implemenation of a CAPTCHA. Its very easy to integrate, without any third party libraries.

What’s The Purpose?

A reCAPTCHA can keep malicious software/bots from engaging in abusive activities on your website while allowing legitimate users access to your site.

How to Integrate?

We will be using the v2 version.

1. Create a site key

You can create a site key from Google reCAPTCHA Admin Page.

You also will need to add a site domain, where you would deploy the site. For testing you can add localhost and use the loopback address (127.0.0.1) or use a key from reCAPTCHA automated tests guide. One of those keys is

6LeIxAcTAAAAAJcZVRqyHh71UMIEGNQ_MXjiZKhI

which we will use in our example.

2. Add Widget to Markup

The only thing we will need to add to our HTML is

<div
  class="g-recaptcha"
  data-sitekey="6LeIxAcTAAAAAJcZVRqyHh71UMIEGNQ_MXjiZKhI"
>
</div>

this can be added to a form or used without one, depending on the use case. Source

We will also need to add a cdn link to the head tag.

<script src="https://www.google.com/recaptcha/api.js" async defer>
</script>

We can listen to callbacks from the widget and register our own handlers.

<div
  class="g-recaptcha"
  data-sitekey="6LeIxAcTAAAAAJcZVRqyHh71UMIEGNQ_MXjiZKhI"
  data-callback="onRecaptchaSuccess"
  data-expired-callback="onRecaptchaResponseExpiry"
  data-error-callback="onRecaptchaError"
>
</div>

these callbacks can be used to validate or invalidate our form or whatever we want to do.

I made a simple form that submits successfully when the reCAPTCHA validates successfully, its here. I also added some basic styling to have a decent look and feel.

Hope this helps you in your Projects. Thanks for reading 😉.