Test out Google reCAPTCHA with PHP by using the no captcha reCAPTCHA, then click "Verify Response" to see if it is correct.
To start using the Google reCAPTCHA PHP class, follow these steps below.
Download the ZIP file with all the files from the Github recaptcha repository.
There is a main class.recaptcha.php file and then a class.http.php file. Copy both files over to where you want to use it.
Add your domain(s) to get a site- and secret key for Google reCAPTCHA.
The example file is index.php which shows you how to use the reCAPTCHA PHP class.
Here is a quick example on how to use the class, it really is easy!