Converting a few documents by hand is one thing, but what if you want to convert a hundred—or a thousand—web documents to XHTML? You can partially automate this process by using automated tools like HTML Tidy and Dreamweaver extensions.
HTML Tidy, a free, standalone, W3C-approved tool, can automatically convert your web pages from uppercase to lowercase markup, your font tags to equivalent style sheet rules, and more. Originally developed by HTML 4's primary author Dave Raggett, Tidy is now maintained as open source at SourceForge (tidy.sourceforge.net). As its name implies, Tidy can clean up your code, point out problem areas, and pretty-print your (X)HTML. Tidy is quite powerful, so be sure to read the manual and make a backup before you tidy up your code.