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HTML Tidy - http://www.w3.org/People/Raggett/tidy/
Unix, Windows, MacOS, and others. Validator fixes errors in HTML and XHTML. Converts HTML to XHTML. Free Software. |
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CSE HTML Validator - http://www.htmlvalidator.com/
Windows. HTML, XHTML, and CSS validator. Also checks accessibility, links, and spelling. Commercial pro version and free lite version. |
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http://jclark.com/sp/ - http://jclark.com/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. |
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Firefox extension HTML Validator - http://users.skynet.be/mgueury/mozilla/index.html
A W3C Tidy-based HTML Validator which checks pages from within the Firefox web browser. |
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WebLight - http://illumit.com/Products/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. |
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HTML PowerTools - http://tali.com/
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. |
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Demoroniser - http://www.fourmilab.ch/webtools/demoroniser/
Perl script which corrects incompatible HTML generated by Microsoft applications. |
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LinkScan/QuickCheck - http://elsop.com/linkscan/
Unix and Windows. Lint and link checker. Commercial software; free trial. Also online checking. |
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HTML Code Cleaner/Compressor - http://www.htmlcodecleaner.com-http.com/
Windows. Optimizes HTML documents removing unnecessary HTML code while checking links. Commercial software with free trial. |
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SP Instructions - http://ktmatu.com/info/do-it-yourself-offline-html-validator/
Windows. Instructions for the Do-it-yourself Offline HTML Validator using SP. |