Google Launches Invisible reCAPTCHA

Three years ago Google introduced its new reCAPTCHA v2 API, replacing distorted text challenges with a simple “I’m not a robot” checkbox for validating users. This was a welcome improvement over the fuzzy text in a box that frustrated and infuriated real humans. reCAPTCHA v1 is no longer supported as of May 2016 and most sites have moved on to use v2. WordPress.org was one of the early adopters of reCAPTCHA v2 and still uses it to validate users on its registration form.
The evolution of reCAPTCHA technology continues, as Google opened up registration for its new Invisible reCAPTCHA today. With the exception of the “Protected by reCAPTCHA” badge on forms, the newest implementation is invisible. It doesn’t require the user to click anything. Invisible reCAPTCHA validates users in the background and is invoked when the user clicks on an existing button on the site. It can also be invoked by a JavaScript API call. If it deems the traffic to be suspicious, it will require the user to solve a captcha.
Invisible reCaptcha for WordPress
Invisible reCaptcha for WordPress is the first plugin to implement the new API. It was launched in December 2016, shortly
Source: https://managewp.org/articles/14560/google-launches-invisible-recaptcha

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