Google reveals invisible CAPTCHA

Google has developed a new "invisible" version of its reCAPTCHA "I'm not a robot" check-box that can verify individuals as human without the user needing to click a button.

The invisible reCAPTCHA sorts malicious bots from legitimate human web traffic behind the scenes via machine learning and “advanced risk analysis”.

The tools study a user’s browsing patterns and decide whether or not the individual is flesh and blood, Google said.

It has not detailed specifically how the technology works, presumably to avoid helping spammers to bypass it.

“To stay one step ahead of the bad guys, reCAPTCHA has to keep evolving to ensure the most delightful user experience,” the company said.

“Human users will be let through without seeing the ‘I'm not a robot’ checkbox, while suspicious ones and bots still have to solve the challenges.”

However, if the invisible reCAPTCHA determines the visitor is suspicious, it will present various challenges for the bot or user to solve.

The new approach will be available on both desktop and mobile.

Google says reCAPTCHA is the most widely used method for filtering bot traffic.