When editing HTML it's easy to make mistakes. Wouldn't it be nice if there was a simple way to fix these mistakes automatically and tidy up sloppy editing into nicely laid out markup? Well now there is! BBTidy is a BBEdit (and BBEdit Lite) plugin for Mac OS designed for doing just that. BBTidy checks and corrects HTML and XML to make it compliant with the Worldwide Web Consortium (W3C) HTML standards.
BBTidy also works great on the atrociously hard to read markup generated by specialized HTML editors and conversion tools, and can help you identify where you need to pay further attention on making your pages more accessible to people with disabilities.
BBTidy is able to fix up a wide range of problems and to bring to your attention things that you need to work on yourself. Each item found is listed with the line number and column so that you can see where the problem lies in your markup. BBTidy won't generate a cleaned up version when there are problems that it can't be sure of how to handle. These are logged as "errors" rather than "warnings".
BBTidy corrects the markup in a way that matches where possible the observed rendering in popular browsers from Netscape and Microsoft.