Validate HTML & CSS With Firefox

Making sure your pages validate is a snap with the Firefox Web Developer Toolbar Extension.

Many web development applications bundle in ways to check your page markup. Both Dreamweaver 8 and TopStyle Pro (tools I use daily) have this functionality built-in, or you can also use nifty online tools, like those at W3C:

• Validate HTML
• Validate CSS

If your web development tools don’t have built-in validators, or you’d like a second opinion, the Web Developer Toolbar offers an easy way to validate HTML and CSS (among many other things) from any page on the web.

To validate HTML or CSS

1. Use Firefox to browse to the page you’d like to validate
2. Click the Tools button in the Web Developer Toolbar
3. Select the appropriate item (Validate HTML or Validate CSS).

The Toolbar will connect to the right validator at the W3C site and output your results automatically in a new tab.