Quantcast, Compete, comScore Offer Differing Views on Facebook’s US Traffic

Web analytics firms Quantcast, Compete, and comScore have all recently released updated numbers on Facebook’s US traffic, but they each differ from each other and from Facebook’s self reported numbers. Why? Each service uses different methodologies with different strengths and weaknesses – usually based on some combination of self reporting, ISP reporting, and panel sampling – but together, we can use them to triangulate trends in Facebook’s actual US traffic.

Here’s the latest from each:

1. Quantcast

Quantcast is reporting Facebook’s August US traffic at 94.6 million uniques, up about 6% since the beginning of July, and up about 150% since this time last year.

2. Compete

Compete is reporting Facebook’s US August traffic at 120.6 million uniques (just to www.facebook.com), up from 117 million last month and 40 million a year ago – but down from its extremely rapid US growth earlier this year. Compete’s numbers are well above those reported by any other firm, or Facebook.

3. comScore

According to comScore, traffic to www.facebook.com grew by nearly 14% month over month in July to over 87.7 million US uniques – the highest monthly growth rate Facebook has experienced in the last year according to comScore.

4. Facebook Itself

Finally, Facebook itself reported 81.2 million monthly active users in the US at the end of August in its advertiser tools. While this number is not real-time, it does generally provide a floor for comparison against third party metrics providers.


All the numbers tell similar stories, just in slightly different ways. Facebook’s US audience is up by over 100% in the past 12 months, and is growing 4-10% each month still, depending who you ask.

As an important aside, measure of Facebook Connect integrations on third party sites can throw off many third party Facebook metrics. Because thousands of sites have implemented Connect (and thus have code loading from a facebook.com subdomain like connect.facebook.com), many more US website visitors traffic all facebook.com domains than just the main Facebook website, www.facebook.com. Each of the firms says they have taken that into account in their numbers above.

Chart: Social Networking US Audience Numbers, July 2009

Source: comScore Media Metrix

Chart: Weekly Share of Visits to Facebook and MySpace within Social Networking Category

Source: Hitwise