by michaelkjeldsen on WordPress.org

Input screen with an example of an Optimizely Project Snippet ID inserted. Yup, that's just about it.
This plugin let’s you easily add the Optimizely Project script to all your WordPress pages. Simply copy/paste the snippet ID from the experiment on optimizely.com into the input field, save settings and you’re up and running.
Yes, it’s as easy as that.