@Judy, yes, it's a paid program i.e. one has to upgrade his/her membership account paying a certain fee (for accessing the entire analysis report and other important features) but you do can use it for free too (although it will have certain limitations). Register yourself using an email id over there and then upon entering your website's url in the tab on the homepage, it will generate an analysis report. However, for free users, it will only show a certain number of details ( I guess 5 or 6) in the analysis report and the rest of the details and features would be locked.
But still then, even the free registered members can find enough helpful details in their report.