Convert Experiments™ provides advanced A/B and Multivariate Testing functionality for your website or blog.
Visit the Convert Experiments™ Registration Page
Log into your account at Convert.com. From your project dashboard, click the settings link and you can see Account details. Your project number will be visible there (see screenshot-1). Your project number will look something like 1000000_1234567.
If you have a caching plugin installed make sure you refresh the cache to display the code. Pay attention to this when using WP Super Cache, W3 Total Cache or any other caching plugin.