SearchPath Blog: AJAX and Search Engine Optimisation (SEO)

Tuesday, October 16, 2007

AJAX and Search Engine Optimisation (SEO)

AJAX has a bad rap in SEO, for obvious reasons – it makes for pages that can’t be indexed. Most AJAX articles relating to SEO mention that you need unique URLs (but not too many), and the back button needs to work. Well, that’s only half the story, AJAX content itself cannot be indexed by Google because it doesn’t exist until after the page has been displayed.

So what can you do about it? Well the simple answer is to not let AJAX run the whole web site; AJAX is best used to enhance the user experience. Here are some simple rules to follow:

Is the content critical? If yes, don’t use AJAX.
Is the information useful, and dynamic? Use AJAX.

In essence Google (and any other search engine) does not click on links. This is very important to realise, Google simply follows any content within ‘href’ attributes. This means if there is nothing in an href, Google will not find it. This has ramifications for .NET applications too, since they often rely on postbacks which Google will not perform.

In essence all important content should be static on the page, while superfluous yet useful functionality and information should be AJAX. If a piece of content falls between these two extremes, try using straight JavaScript. By having a hidden div, the content is still on the page, but not visible until necessary. Don’t over-use this latter technique; otherwise Google may think you’re hiding content with the intention of gaining ill-gotten rankings.