Site validation is an important tool to use when designing a website. Having valid code means your site is much more likely to work as you intended in different browsers and on different computers. By validating your site, you can check the HTML, XHTML and CSS for syntax errors and compliance to established standards.

Resources that can be used for validating your site:

• W3C Markup Validation Service: An free online service that validates validates HTML or XHTML in one of three ways: you can enter a page URL, upload a file or paste code directly in the validator.
• W3C CSS Validation Service: A free online service that validates CSS.
• Feed Validation: A free site to validate your RSS feeds.