| A Real Validator: Windows. Based on an SGML parser. Shareware. |
| CSE HTML Validator: Windows. HTML, XHTML, and CSS validator. Also checks accessibility, links, and spelling. Commercial pro version and free lite version. |
| Demoroniser: Perl script which corrects incompatible HTML generated by Microsoft applications. |
| Firefox extension HTML Validator: A W3C Tidy-based HTML Validator which checks pages from within the Firefox web browser. |
| HTML Code Cleaner/Compressor: Windows. Optimizes HTML documents removing unnecessary HTML code while checking links. Commercial software with free trial. |
| HTML PowerTools: Windows. Includes validator, image scanner, meta tag manager, find and replace tool, tag pair fixer, and an HTML to text converter. Commercial software; 30-day demo. |
| HTML Shrinker: Windows. Removes unnecessary characters from HTML, CSS, Perl, JavaScript and many other web file formats. Commercial pro version and free light version. |
| HTML Tidy: Unix, Windows, MacOS, and others. Validator fixes errors in HTML and XHTML. Converts HTML to XHTML. Free Software. |
| LinkScan/QuickCheck: Unix and Windows. Lint and link checker. Commercial software; free trial. Also online checking. |
| SP: Windows and Unix. Object-oriented toolkit for SGML parsing and entity management. Can validate any version of HTML for which a DTD is available. Free Software. |
| SP Instructions: Windows. Instructions for the Do-it-yourself Offline HTML Validator using SP. |
| SWAN: SubWeb Analyzer: Unix. Generates statistics and finds inconistencies in a subweb (web site). |
| WebLight: Linux, Mac OS X, and Windows. Finds broken links, non-standard HTML, and links between URIs on web sites. Commercial software; free for small sites. |
Classical
