The Alexa traffic rank is calculated using a combination of average daily reach and pageviews. What is "reach"? We'll have more to say about this in an upcoming post, but basically it measures how many people are visiting a site, expressed as a fraction of the global Internet population. For example, if you click on the "Reach" link below the "Traffic Stats" tab, you can see that Google's reach is currently around 33%, meaning that about one in three Internet users visit google.com on a typical day.
As the site with the highest combination of reach and pageviews, Google is currently ranked #1. The site with the second highest combination is #2, the next is #3, and so on. The best way to improve your Alexa traffic rank, that is to get a rank that is a smaller number than you have now, is to attract more visitors to your site and keep them engaged (and clicking) on more pages. Note that reach is weighted more heavily than pageviews in the combination, so other things being equal, the former (adding visitors) counts for more than the latter (adding pageviews per user).
The main Alexa traffic rank (as displayed in the Alexa toolbar) is a three-month rolling average, while the points in the Traffic Stats rank graph are daily. While the daily Alexa Traffic Ranks allow you to see fluctuations in a site's traffic on a very short timescale, the longer-term averages listed on the site information pages (and used for our Top Sites lists) are much more robust and authoritative for sites with low traffic. Note that ranks above about 100,000 should be taken with a healthy grain of salt and are not displayed on our graphs.
When looking at a Traffic Rank graph, what are some if the things you see? For some sites the first thing you might notice is an approximate 7-day periodicity in the data. This is because the "weekend web" is a little different than the weekday web, and some sites are less popular (or more popular) destinations on the weekend. You can clearly see this effect in the traffic graph for LinkedIn, the popular networking site for professionals.
Another feature you can see in traffic rank graphs is how a website's rank is trending over time. The three-month average is just that, a rank based on the accumulated reach and pageviews over the course of three months. Facebook, for example, recently moved ahead of YouTube and into the number three position. But this reversal happened a while ago in both the daily traffic rank estimates and in the one-month traffic rank. We can also see that Facebook is continuing to grow, and it could soon overtake #2 Yahoo (which until 2009 had long been #1).
What is all this good for? Well, at some level it is fun and interesting. The fact that Facebook is on any given day globally the 3rd most popular destination in the world says a lot about what people are using the web for. This pattern is not limited to just Facebook, either, but other community sites such as Wikipedia, Blogger, and Twitter, all all trending upward as well. People are using the web to connect with each other, and while this is not a new revelation it certainly is apparent in the data.
This analysis doesn't have to be limited to social networks or top sites, either. If you own a website, you can use Traffic Rank to compare your site to those of your competitors. Does the competition have a better (lower) rank than you? If so, you can start asking yourself why they are getting more visitors and/or pageviews, and what you can do to improve your rank in relation to theirs. Be careful, though. Even if your Alexa Traffic Rank is better than your competitors, that does not necessarily mean you are getting more of the quality traffic you want. For that you need to delve further into the Traffic Stats graph, which we will do in the next installment of this series.
