Validation supports usability & SEO

Valid code for both markup (e.g., HTML, XHTML, etc.) and CSS is a basic necessity not only to ensure that browsers are able to display a working webpage (users typically don’t hang-around broken pages for too long), but also to make it easy for Search Engines to understand what your site is all about.

It is surprising then, that one of the most common issues that we’re finding in our initial analyses of clients’ websites is that their markup is chock full of errors. These days, with the availability of free code validation services online for markup, CSS, and more, there’s no excuse for having invalid code on your site.

Free validation services = no more excuses

Although there are a number of sites providing free validation services, I always find myself returning to the place where web code standards are king–the World Wide Web Consortium, otherwise referred to as the W3C.

The W3C offers a number of excellent validation tools that are simple, fast, and provide detailed explanations of errors and warnings.  Just type in your site’s domain and let the validator work its magic.  In my experience, even when I was unfamiliar with a solution to a specific issue, the information provided by the W3C’s validator was sufficient ammunition for searching out some help in “forumland”.

In addition to the Markup and CSS Validators, I also highly recommend using the W3C Link Checker (links below).

Links to free, online validation tools

W3C Markup Validator
http://validator.w3.org/

W3C CSS Validator
English: http://jigsaw.w3.org/css-validator/
简体字: http://jigsaw.w3.org/css-validator/validator.html.zh-cn

W3C Link Checker
http://validator.w3.org/checklink

Happy Validating! :-)

Adam
Co-Founder & VP of Services
打开后天SEO&Design