Jetpack makes it easy to add contact forms to your WordPress site, but you may want a simple way to add a Google reCAPTCHA to prevent spam. This plugin will manipulate the Jetpack [contact-form] shortcode to prepend the Google script, add a button, and parse the response. This plugin allows both reCAPTCHA v2 and invisible reCAPTCHA (see screenshots and choose whatever works for you!). Shoot me a question about it on Twitter: @bozdoz. This plugin is open source on GitHub!