Does Google Read Your CSS Files?

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Does Google Read Your CSS Files?

In the past, everyone knew that Google and the other engines, stayed away from your CSS files. However, after on October 19th, Matt Cutts posted a blog entry named SEO Mistakes: Unwise comments which showed an example of someone using CSS. Matt wrote;

I don’t recommend that people use CSS to hide text, and I don’t recommend that they document it, either.

Then Jagger update hit us, and many now believe that Google does peak at your CSS files. A DigitalPoint Forum thread asks Does google read external CSS files yet? Some reply “no” right off the bat, but I wouldn’t be so quick to say no. Many respectable SEOs have been chattering about Google reading your CSS just for this. So just be careful, especially now.

Barry Schwartz is the Editor of Search Engine Roundtable and President of RustyBrick, Inc., a Web services firm specializing in customized online technology that helps companies decrease costs and increase sales.

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  • Sean Fraser

    I beleive that a better question would be “What does Google read in external CSS files?”

    Google has always read external CSS files! How else would every CSS based site (that meets Accessibility and Standards) be rendered with format and images in Google.

    Search Engine Journal is XHTM/Transistional with tables for presentation; my site’s XHTML/Strict with an external style sheet for presentation. Google reads your HTML presentation; Google reads my CSS presentation. They are each rendered perfectly.

    The question – Then – is what changes has Google made regarding “hidden text” caused by an image replacement technique.

    Or, what how does Google read on-pages links like “Skip Navigation” or “link rel”? Or, what does Google do to a site where pages are fed mutlitple style sheets like “High Visibility” or “Print Version” or “Handheld Version”?

    Some of the more progressive CSS sites have three sets of external style sheets in the header, two @import style sheets in those and one or two IE conditional comments in the head section. They do just fine in Google. And, Everywhere else, too.

    External style sheets get read.

  • Nanobot

    Looking through my log files, I don’t see a single instance of Googlebot requesting any CSS files. Perhaps it’s only doing it for sites that “look” like they may be trying to trick a search engine, like if a ton of keywords are just listed on a page. I don’t know, but it sure doesn’t seem to be looking at the CSS of all sites.

  • Thomas

    Umm…. why would they? Doesn’t Google care about on page and source information? The CSS just makes it prettier to humans.

  • Mel

    There is no need for Google to read your CSS file to display your site in their cache (which I believe is what Sean is saying) any more than they have to download all your images to make your site display properly. Both the CSS and the images are called from your server.

  • Domus Italica

    The trick here is to use html tags for the crawler and css for humans. You can’t add keywords to a css file anyways so does it matter?

  • Michiel

    Google does read your css and can ban you because of it; for more info , read
    my post at digitalpoint.

  • Ogaden

    Well what about the use of PHP or any other scripting language as your CSS? This will overcome most problems that have been mentioned above, right?

  • Affiliate Business Mentor

    I have seen google request my CSS files on some of my websites, but I don’t know for sure if it parses them.

    Someone mentioned why would google bot look at your CSS as you can’t hide keywords in the CSS file. No, you can’t hide keywords in CSS file, but you can make a DIV full of keywords and hide it under your actual content using CSS, making your content very keyword rich, yet presenting your viewers with different visual, they won’t see a clutter of keywords listed out, but the search spiders will. Ranking you higher. Until they discover this, then drop all your indexed pages.

    I have also seen people having AdSense content websites and using a DIV to cover the “Ads by Google” on the Ads making them look more natural to your viewers. This is also against AdSense TOS.

    So yes Google does have a reason to parse your CSS files and render the CSS to see if content is being covered whether it is “Ads by Google” or a hidden DIV full of keywords.