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Google reCAPTCHA Spam Protection

reCAPTCHA is a free service that protects your website from spam and abuse. reCAPTCHA uses an advanced risk analysis engine and adaptive challenges to keep automated software from engaging in abusive activities on your site. It does this while letting your valid users pass through with ease.

In Backlight, you may configure the v2 and v3 versions of reCAPTCHA simultaneously, then choose which to use for individual forms. There are various reasons to use one over the other.

About reCAPTCHA v2

reCAPTCHA v2 displays a checkbox, reading "I'm not a robot", that must be checked in order to submit the form. Because the reCAPTCHA requires interaction, it is the suitable choice for contact forms that may require more than two minutes to complete.

About reCAPTCHA v3

reCAPTCHA v3 does not display the not-a-robot checkbox, instead verifying legitimacy without any user interaction. It's convenient, but also includes a two-minute timeout. If your form may take longer than two minutes to complete -- such as writing a message in a contact form -- then reCAPTCHA v3 may not be suitable for your form.

reCAPTCHA v3 generates a score for interactions, and uses that score to determine what to do with the submitted form.

Backlight provides a facility to review spam messages so that you won’t miss legitimate messages that get caught out. The recommended score threshold of 0.7 is based on our application developer's real-world experience running another site with tens of thousands of visitors.


To get started, visit Google reCAPTCHA. Access the admin console, and configure your desired version of reCAPTCHA for each website on which you intend to use it.

Back in Backlight, visit Admin => Settings. Scroll down to location the section "Contact Forms Spam Protection". Set the Site Key and Secret Key for your respective version(s) of reCAPTCHA.

reCAPTCHA can be enabled and disabled for each Contact Form. To enable reCAPTCHA, visit Designer => Contact Forms and click edit for the form you wish to add reCAPTCHA to. Change the setting for Enable reCAPTCHA and click save.

Problem Solving

Backlight provides a setting to display error messages in the case that you find reCAPTCHA failing to accept a form submission when it should. To enable this setting, visit Backlight => Settings, scroll down to "Contact Forms Spam Protection", and enable the "Debug reCAPTCHA" option. If the resulting error message on form submission does not help solve the issue, then please ask for assistance on our forum.