Checking your website's code with a HTML Validator

HyperText Markup Language (HTML) is a coding standard with a reasonable degree of complexity. HTML standards develop over time, and a valid HTML code displays more websites more accurately in a wider range of browsers. Sites that have substantial amounts of HTML coding errors can potentially be punished by search engines. For this reason, you should periodically check your website for HTML coding errors.

There are two principal tools that web professionals use to check the quality of their websites' code: the W3C HTML Validator and the CSE HTML Validator.

The W3C HTML Validator (http://validator.w3.org) is the less robust of the two validators, but it is free. Both validators work in the same way: they examine the code on your website and issue a report advising you of any errors.

The CSE HTML Validator (http://htmlvalidator.com) is not a free tool, but you can get a free trial of the software that is good for 30 days or 200 validations...