The W3C HTML Validator below shows error types when parsing the page with an SGML parser; Runs WebLint HTML syntax and minimal style checker; and creates a parse tree. It opens in a new window.
AnyBrowser - Site Viewer lets you see HTML pages as other browsers would, or in different screen sizes. Link Checker for 1 static page at a time. HTML validation, and other website tune-up tools.
Bobby - Analyzes web page for browser compatibility and accessibility to people with disabilities. Also available as program to download.
Cyan - Online interface to the HTML validator and beautifier, W3's HTML TIDY. Check web page for HTML 4 compliance while formatting tags according to your preferences. Lets you download a copy of the specified web page with common errors fixed, and points out rest of the errors.
Delorie - Web page backward compatibility viewer.
Delorie - Web page purifier - view a page which has been "purified" to be compliant with a choice of various HTML standards, including Web TV 1.1.
Dr. Watson - HTML validator which checks syntax, links, search engine compatibility, link popularity, estimated download speeds, and more.
Eons - Screen resolution tester - test your web pages in different screen resolutions and window dimensions.
Eons - Web TV test - see what your pages looks like on Web TV (requires Microsoft Internet Explorer).
Hitbox - Check HTML syntax, META tags, spelling, load time, broken links, and reduce image sizes.
HtmlHelp - WDG HTML validator - validate 1 URL, 1 page from your computer, list of URLs (batch mode), pasted HTML, or entire site.
Imagiware - Doctor HTML (Web page analysis tool) and HTML page squisher.
LinkAlarm - Trial 100 points (pages). Checks every link on up to first 100 pages of website, up to once a day, and emails a report. Has an affiliate program to earn money, or more points for continued service. Additional points only 1 cent each. To conserve points, you can specify particular page(s) or directory(s) to check. Recommended.
LinkScan - Verify Links and check HTML syntax with WebLint of 1 URL at a time.
Meta Medic - Checks description and keywords meta tags for search engine acceptability. See their free search engine tutorial.
NetMechanic - Check links, HTML (repairs), load time, spelling, and more. Choose 1 or 5 pages, and monthly tune-up report. Compress JPEG and GIG images. - Recommended.
OptimizeItHere - GIF Cruncher & JPEG Wizard shrinks GIFs and JPEG images.
SiteOwner - Check HTML links and spelling.
SpellOnline - Spelling corrector for text or HTML - 5 languages available.
WebsiteGarage - Free webpage tune-up to check for broken links, spelling errors, browser compatibility, and reduce your image sizes - Recommended.
Scripts & Programs
ARealValidator - HTML syntax checker for Windows which uses a sophisticated SGML parser - 30 day trial.
BannerCrafter - Create custom animated or static animated banners or images, for Windows 95/98/NT4).
Bobby - Analyzes web page for browser compatibility and accessibility to people with disabilities. The program can check multiple local files or entire web sites at one time. Available in several platforms, including generic Java.
CyberSpyder - 60-day trial shareware - Link verifier with several nice features.
GIF Cruncher - 15-day trial - Compress GIF images, single or batch mode.
Html-Kit - HTML & text editor with GUI interface for W3C's HTML Tidy Validator for HTML, XML, and CSS. Editor has many features such as spell checker and thesaurus. For Windows 95/98/2000/NT4.
HTML Compressors - List of 7 free HTML compressor programs to make your webpages load faster (keep the uncompressed version to edit though).
HtmlValidator - CSE HTML validator for Windows 95/98/2000/NT - Recommended.
InfoLink - Link verifier for Windows 95/NT- trial version (50 evaluation runs).
JPEG Wizard - Edit and shrink JPEG images without recompressing.
Linbot - Site management tool written in Python - Verify links, view site structure, and find website problems.
LinkLint - Perl (4 or 5) trial/shareware program to check HTML links on Windows and Unix platforms.
LinkScan - Verifies links (over 40,000 links/hour!), validates HTML, and creates sitemaps (requires Perl 5 and Linux, Unix, or Windows NT/98).
Mathew's Webtools - Perl and shell scripts to validate HTML, fix spelling, and validate links.
SiteMapper - 14-day trial demo (checks up to 250 links per URL) - Creates a sitemap and verifies hyperlinks for 1 page, directory, subdirectories, or entire website.
SP - SGML parsing and HTML validation - available as C++ source code or binaries for Windows 95/NT, MS-DOS, Unix, Linux, Solaris, and others.
Tali - HTML Power Tools - 30 day trial - available in both Windows 3.x (16-bit) and Windows 95/98/NT/2000 (32-bit) versions - checks HTML for errors in any or all browsers, verifies links, weed out obsolete files, do site search and replace, and much more.
TetranetSoftware - LinkBot Pro - 15-day trial - HTML validation, scans a website and detects over 50 different website problems, verifies links, parses flash files, website search and replace, and much more.
W3 - HTML Tidy - Fixes HTML mistakes automatically and tidy up sloppy editing into nicely laid out markup.
WebLint - HTML syntax and minimal style checker. A Perl script which picks fluff off HTML pages.
WebTV Viewer - Simulates WebTV on your personal computer, for Windows 95/98/NT or Macintosh.
Xenu's Link Sleuth - Spidering software to find broken links and make site map, for Windows 95/98/NT/2000.