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CSS HTML Validator
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<p>CSS HTML Validator (previously named CSE HTML Validator) is an <a href="/facts/HTML_editor/Tf82QUku">HTML editor</a> and <a href="/facts/CSS/tA90XBQo">CSS</a> editor for <a href="/facts/Microsoft_Windows/bwhAhuSL">Microsoft Windows</a> (and <a href="/facts/Linux/9FvCKSTq">Linux</a> and other <a href="/facts/Unix-like/YAKrAxzd">Unix-like</a> operating systems when used with <a href="/facts/Wine_(software)/JF0wHs7y">Wine</a>) that helps web developers create syntactically correct and <a href="/facts/Accessibility/hp9gz5GK">accessible</a> <a href="/facts/HTML/sSc3fT78">HTML</a>/<a href="/facts/HTML5/HBAxEAr6">HTML5</a>, <a href="/facts/XHTML/6qHnmJSg">XHTML</a>, and <a href="/facts/CSS/tA90XBQo">CSS</a> documents by locating errors, potential problems like browser compatibility issues, and common mistakes. It is also able to check links, check spelling, suggest improvements, alert developers to deprecated, obsolete, or proprietary tags, attributes, and CSS properties, and find issues that can affect <a href="/facts/Search_engine_optimization/RNzIbb62">search engine optimization</a>. </p><p>CSS HTML Validator is developed, marketed, and sold by AI Internet Solutions LLC located in <a href="/facts/Texas/B987WHF0">Texas</a>. The first version of CSS HTML Validator was released in 1997 for <a href="/facts/Windows_95/1E1L93qC">Windows 95</a>. The current version is 2025/v25.01 (as of January 24, 2025) and is for <a href="/facts/Windows_10/be9IHehJ">Windows 10</a> and above, including <a href="/facts/Windows_11/J2ywV8r4">Windows 11</a>. A native <a href="/facts/MacOS/Y93vVpTm">macOS</a> and <a href="/facts/Linux/9FvCKSTq">Linux</a> command line version (called htmlval) became available with version 23. There are currently three main editions of CSS HTML Validator — Pro/Professional, Home/Standard, and Lite. The Enterprise edition was discontinued in 2025/v25. While the application is generally a commercial product (except for the Lite edition), a free version of the Home edition is available for personal/educational, non-commercial use. A free limited version of the htmlval command line tool for macOS and Linux is also available. </p>