How to enable reCAPTCHA protection against spam in your forms with Nimble Builder?

reCAPTCHA is a free service by Google. Nimble Builder allows you to use it in your forms to protect you against spambots and other types of automated abuse.

You have probably seen this type of checkbox when using a contact form on the web. The idea is to make sure that the entity about to send the form is a human and not a robot.

reCAPTCHA is a CAPTCHA-like system designed to establish that a computer user is human (normally in order to protect websites from bots) and, at the same time, assist in the digitization of books. You'll find more technical details about reCAPTCHA here.

Nimble Builder uses the latest version of Google reCAPTCHA, which has been made invisible. No need to check anything anymore. This version of reCAPTCHA uses sophisticated algorithm to identify abuses. The main idea is that on each form submission, the reCAPTCHA api returns a score from 0 to 1 : 1 is very likely a good interaction, 0 is very likely a bot. The score threshold can be adjusted according to your spambot strategy.

How to enable teCAPTCHA protection with the Nimble Builder ?

Nimble Builder allows you to enable site-wide reCAPTCHA for all your Nimble contact forms. If necessary, you can disable reCAPTCHA on an individual form basis.

1. Access the live customization interface and click on the global settings icon
   
   1. open the Nimble Site wide options panel
   2. expand the reCAPTCHA tab and activate reCAPTCHA
2. sign up for an API key pair for your site : choose type reCAPTCHA version 3. You will need to copy and paste the site key ( 1 on the figure below ) and the secret key ( 2 ).

Monitor and adjust the score for your forms

reCAPTCHA returns a score from 0 to 1 on each submission. 1 is very likely a good interaction, 0 is very likely a bot. Google let you monitor your score with analytics from the admin console.

Nimble uses a default score of 0.5, as per Google recommendations. Depending on your score distribution, you can adapt the score of your form with Nimble score threshold option.

A form submission that scores lower than your threshold will be considered as a done by a spambot, and aborted.

Note : as of November 2019, a problem has been reported ( missing-input-response error message when submitting a form ) when activating reCaptcha both on Nimble Builder and Contact Form 7 on the same website.