Effect of Website Downtime on Rankings
Site downtime is something that webmasters have to worry a lot about, as time when the site is down can mean loss of money, sales, leads, memberships, or a general decrease in whatever conversion goal a site has.
Yet another worry about site downtime is how it may affect Google’s ranking of a site – after all, Google ranks a site based on what it finds while it crawls the site – so if it doesn’t find anything, it can’t rank and index it, right? Thankfully, Google’s Matt Cutts answered this question on a video on the Google Webmaster Help YouTube Channel.
To sum up the answer in a sentence, what Google does depends on how long your site is down. He explains it by asking viewers to look at it from Google’s point of view – you don’t want to keep dead sites in the search results, but you also don’t want to throw out perfectly good websites after a few seconds of downtime. Because there is no real way for the web crawler to know when a website will be back up, it has to try to reach a compromise between the two.
In this case, it means that if the crawler cannot find a site, it will try to crawl the site again soon and see if it is back up. It will try several times to reach the site. While this is happening, the site may temporarily drop in the search result rankings, but is not completely dropped from Google’s index. However if, after several days, Google’s web crawler still cannot access a certain website, then it is forced to conclude that the site must not exist anymore and it will drop the site form the search index.
Presumably the site can be re-indexed, but it will take a bit of SEO and some new links pointing to the domain. Fortunately, Google is somewhat forgiving with temporary downtime, but the lesson of this video for webmasters is that website uptime is important, and that several days of downtime can cause permanent loss of position in Google’s index.