Website Grader puports to analyse all aspects of your website's performance, mobile readiness, SEO and security. Enter your URL, offer up your email address, it loads your site and in a few seconds, rates it on a number of metrics. It is probably quite valuable for spotting large issues, but for finer granular reporting, one would have to look elsewhere. The site's main function seems to be to nudge users towards the parent service, HubSpot Website Platform. But it is beautifully designed, fun to use and readable, so test away.