SEO: The Dreaded Supplemental Index
Did your website used to get a lot of traffic, but now that traffic has started to taper off? Ever wonder why? This could be due to some or most of your pages ending up in Google's dreaded Supplemental Index. Many websites have been faced with this problem, and are desperately doing anything they can to stay out of it.
What is the Supplemental Index? The Supplemental index is a secondary index where Google puts pages that it deems "not that important". It then uses the Supplemental Index only when a user types in a search query that doesn't bring up very many results.
Why Would Google Do That? The reason the Supplemental Index was put in is to lighten the loan on Google's search spiders. In essence, the spiders regularly update content in the main index, but rarely come and index content in the Supplemental Index. It's a way to Google to make sure that the important stuff comes up first and that the important stuff is up to date.
But My Website Is Important Too! What Can I do? There are several factors Google takes into consideration to decide whether a particular page on your website goes into the normal index or the Supplemental Index. Here is a checklist to consider when reviewing your website:
- Make sure each page has a unique title and meta description
- Make sure each page has unique content
- Reduce site-side repetitive features as much as possible
- Make page URLs meaningful
How Do I know If My Pages Are in the Supplemental Index? A simple way to find out this information is to go to http://www.google.com/search?hl=en&q=site%3Awww.yoursite.com+***+-sljktf (Where yoursite.com is replaced with the actual domain name of your website.) This will not only give you a count of the pages in your site, but it will also show you the individual pages in the supplemental index. You can then divide that by the total number of indexed pages to come up with a ratio that you can use to compare to other websites in your industry. You can get this number by going to http://www.google.com/search?hl=en&q=site%3Awww.yoursite.com (Again, replacing yoursite.com with the actual domain name of your website.) Having some pages in the Supplemental Index isn't going to kill your website, but you want to have the least number of pages in there as possible. For instance, Microsoft.com (as of the date I'm writing this article) has a whopping 317,000 pages in the Supplemental Index! Now, that might seem like an overwhelming amount, but if you look at that relative to the total number of pages they have, you're looking at only about 9%. How is the overall health of your website?