Everyone can make a website nowadays. Or at least, that's what we'd like to think. In reality, even though Wordpress and Content Management Systems have made it a lot easier to put up a brochure website or blog, the large majority of websites is still custom-made.

CheckSite is a tool that can be used to find potential problems in HTML. It uses the W3C Validator to validate the page, and then performs a number of additional checks. These checks are "tribal knowledge", things that are not part of an official standard but are known to be best practice.

Checks are divided into a number of categories: browser compatibility (does the page use constructs that are known to cause problems in some browsers?), SEO (does the page adhere to SEO guidelines?), user experience (does the page have a favicon and sitemap?), and internationaliation (does the page use UTF-8 encoding?).

Limitations: 30-day trial.

Requirements:
OS X 10.7+
64-bit Intel