The most common causes for any 'sudden drop' in PageRank

• My homepage recently suffered a PageRank drop. Just prior to that, we added a large number of outbound links and are now wondering if that was the cause. Are there limits to how many links we should have on our pages?

Answer: It's unlikely that adding those outbound links was the cause of your PageRank dropping. A PageRank drop is nearly always caused by a drop in external links pointing to a page, not by the links pointing out from the page. Those incoming links either became partially devalued due to losing inbound links of their own, or they lost their value completely by being removed or having the nofollow tag applied to them.

You should examine your inbound links looking for recent changes. You can do this using our Site Strength Indicator tool (log in with this month's password). Losing high PageRank inbound links (or if those linking pages lost PageRank themselves) is the most likely reason for this sudden PageRank drop. And, because high PageRank links are so important, all it takes to have an adverse effect on rankings is to lose just a few.

Bear in mind that it is also possible to dilute the link juice (PageRank) pointing at your own site's pages by adding a large number of outbound links all at once. This also could adversely effect your PageRank.

However in most cases this does not cause enough of a change in PageRank flow to see any negative effects unless the links you've added are sitewide (i.e. linking out from every page on your site). For example, if you have 5-10 outbound links in the footer of every page on your site, that could have the effect of siphoning PageRank away from your site. In that case, you may want to limit those outbound links to just a few of your pages, such as your homepage, rather than making them sitewide.

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