Umbraco Forms Version 7.x contains reCAPTCHA version 2 field out of the box, so this package needed only for forms 6 or lower There is newer version of reCAPTCHA called Invisible reCAPTCHA ready for use with Umbraco forms, check out - https://our.umbraco.com/packages/collaboration/invisible-recaptcha-field-for-umbraco-forms/
The new ReCAPTCHA field helps protect your Umbraco Forms from bots without having to solve a CAPTCHA. Instead with just a single click they’ll confirm they are not a robot. We’re calling it the No CAPTCHA reCAPTCHA experience.
Thanks to Andy Butland, his post inspired us - https://our.umbraco.org/forum/umbraco-pro/contour/63765-Upgrading-ReCaptcha-to-the-Im-not-a-robot-version#comment-215220
Note: Please make sure that you have installed Umbraco Forms before installing this package.
PS: Now you can use the code of GooglereCaptcha provided by HQ, download it here - http://issues.umbraco.org/issue/CON-941