visibility:hidden and display:none CSS

[Dani]

Someone brought up an interesting point in another thread. Do the search engines look out for the visibility:hidden and display:none CSS the same way that they used to when font color and background color were the same? If so, do they only check inline CSS or do they actually read CSS files? If no, how do you know, and do you think this is something they're most likely going to do in the future?

[jreseo]

Search engines, including Google and Yahoo, will definitely find and index text with display:none and hidden. Lots of examples out there. For example, do a Google or Yahoo and search on

seattle real estate science recreation trulia

You will see this page in spot #1:

http://www.trulia.com/real_estate/Seattle-Washington/

If you view the search engine cache, and click on the "Community Links" section down the page, you will see that both engines find and index content that is in a "display:none" <div>. There are lots of examples like this.

Also, zillions if sites use these techniques for drop down or pop up menus, and these links are followed.

Using such techniques is very common, and great for user experience (keep in mind this is what search engines want: good sites). Simplistic techniques such as white on white were very obvious, and hard to argue where that might be good for users, so easy to filter. Use of display:none and hidden can be great for users and are commonly used, so search engines would be foolish to ignore such content.

The real question here is whether this is some kind of filter or penalty for hiding content, or whether search engines are smart enough to examine the JavaScript and CSS to determine if the page is built to allow this content to be displayed. My belief, though I have no absolute proof, is that they do both. I think that if a site has a high degree of trust (based page rank, good content, few other signs of abuse and other algorithmic factors), hidden content is trusted. If the site does not have trust, it is perhaps given lower weight (i.e., penalized to some extent). I also suspect that they do look at JavaScript/CSS code (in line and in files) and try to interpret that to see if hidden blocks are ever shown -- not too hard to do if you think about it.

The bottom line answer here is the same as always: build for your users using reasonable techniques, and don't stress on what the search engines do. If your stuff does not show up in searches, then look deeper for the reason and experiment with removing hidden content to see if you triggered some penalty.

John Erickson

[davidgeo]

Search Engines do crawl and index, hidden and none texts. but it doesn't show up longer time, as search engines become wiser enough they would penalize you are even ban you from their SERP's

[adgraphics]

Search Engines do crawl and index, hidden and none texts. but it doesn't show up longer time, as search engines become wiser enough they would penalize you are even ban you from their SERP's

This is not likely to happen as most websites these days are very heavy using WEB 2.0 and 3.0 which uses a lot of DOM scripting which requires display:none and visibility:hidden. THOUGH if you have suspicious content stuffed in such blocks then I see a problem. really these blocks are no different than standard html so don't spam in them! :o)

[wickedsunny]

well they do actually coz they take the contents from the source code