CSS validators apply current CSS standards to referenced CSS documents.To make it easy to use the W3C validators, paste the following HTML code into your page's code.

validating css and xhtml-22

The only way to ensure that pages always display as intended is to test them in all browsers expected to render them correctly.

While the W3C and other HTML and XHTML validators will assess pages coded in those formats, a separate validator like the W3C CSS validator can check that there are no errors in the associated Cascading Style Sheet.

While many veterans have learned to create error-free code and make relatively few validation errors, most beginners make more errors.

Computer validation checks can help beginners learn from their mistakes.

Mark-up validators cannot see the "big picture" on a web page, but they excel at picking up missed closing tags and other technicalities.

DTD-based validators are also limited in their ability to check attribute values according to many specification documents.For example, using an HTML 4.01 DOCTYPE, bgcolor="fffff" is accepted as valid for the "body" element even though the value "fffff" is missing a preceding '#' character and contains only five (instead of six) hexadecimal digits.Also, for the "img" element, width="really wide" is also accepted as valid.Websites that are not validated may display correctly in one browser but not in other browsers. Websites that are not validated may display formatting problems when used in certain browsers.On the other hand, W3C validated websites are displayed without errors regardless of what browser is used.Unfortunately, many website owners do not take advantage of this growth and forego W3C validation that makes sure their websites and web pages are mobile friendly too.