Advanced Testing Center
Use the testing center to see how your email will look in various email clients. Go to Analyze, Campaigns, Advanced Testing Previews:
Once you are at the list of emails, select “Preview” from the drop-down menu to the right for the individual campaign in the list.
This section will render an approximation of how your email will look in various email clients. The results are usually very good but be aware there can be minor differences between the previews and how the email renders in individual email clients, especially due to settings that may be in place on the end-user’s device. It’s a good idea to look at the email clients you expect your users to be using when they open your email to make sure your layout looks good.
We submit the email to Litmus for spam diagnostics. This section will give you a pass/fail notification for some areas like DKIM or SPF setup, and a score for other areas like Barracuda or Spam Assassin. To interpret the scores associated with each spam diagnostic, please refer to the Litmus documentation.