Web Lint

This tool checks HTML and XHTML pages for possible markup problems. It attempts to find problems with your code that an HTML validator does not: your page should be valid (or nearly so) before starting with this tool.

Like all lints, this tool checks for suspicious constructs in your code. You may find that it flags things that you consider correct: that is okay. The goal with this tool isn't necessarily to get zero warnings, but to consider the warnings presented. As the “level” gets higher, it is more likely that you will decide to ignore the warnings: you should just be sure you're making an informed choice.

Simply give a page you want to check and see what it finds…

Check By URL

Check By File Upload

Check By Direct Markup Entry