How can I protect my website contact forms from abuse using a CAPTCHA?

Our service is often used with website contact forms. Automated bots regularly target these forms to send spam to the webmaster or, if the form permits, a named recipient. A CAPTCHA can help prevent this abuse.

A CAPTCHA (Completely Automated Public Turing Test) is a function that uses a series of images or questions that the user has to respond to in order to verify that they are a human before the form can be submitted.

We would recommend that you use the free CAPTCHA service provided by Google called reCAPTCHA.

Google provide extensive developer documentation with many code examples including a PHP library, this can be used in conjunction with PHPMailer which is a library that can be used send email via our service from a PHP based website.

You can find the necessary resources to add a CAPTCHA to your form here:

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