The Blogosphere By the Numbers

The size of the blogosphere has doubled every five months over the last year and a half, according to blog analysis firm Technorati. Over that time, blogs have gone from being a word that sounded insulting to an online trend embraced even by a sexagenarian Massachusetts senator running for president. Given the frenetic pace of that growth, data charting the blog phenomenon have been vigorously consumed, and in some cases contradictory.

In charting the scope of this trend, ClickZ sought out the most helpful metrics for understanding the expansion of the blogosphere, a topic we’ll return to periodically.


According to David Sifry, Technorati’s chief executive, the current number of blogs is now over 8 times bigger than the 500,000 blogs it measured in June, 2003. The company tracked 3 million blogs as of the first week of July, and has added over 1 million blogs to its stable since then. Meanwhile, Pew Internet & American Life reports a new weblog is created every 5.8 seconds. That roughly translates into 15,000 new blogs every day.

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In an announcement dated November 18, blog-search company PubSub Concepts claims to already monitor over 6.5 million blogs. Perseus Development, meanwhile, estimates by the end of 2004, there will be 10 million blogs, the vast majority already dead.

ClickZ interrupted Weblogs Inc. founder Jason McCabe Calacanis’ trip to China for another perspective.

“There are millions of blogs, but I would say less than 1 million are updated regularly,” Calacanis emailed. “So less than 1 percent of the country is blogging, but that figure is going to grow over the next five years to some percentage of the folks who email today.”

While he was über-exuberant enough to predict that percentage will be 50 percent of the number of daily email users by 2009, the point about the number of regularly updated blogs is easier to substantiate.


Let’s start with Calacanis’ other calculation. According to the former editor-in-chief of the “Silicon Alley Reporter,” there are only 200 blogs with monthly traffic of 1 million pageviews per month. Only 20 of those receive over 10 million pageviews per month.

In terms of viewership, the Pew Internet & American Life Project estimates about 11 percent (approximately 50 million) of Internet users are regular blog readers. Active bloggers, meanwhile, update their blogs regularly, to the tune of more than 275,000 posts daily, or about 11,000 updates an hour.

Blog traffic is known to spike sharply when certain Web-communicable events occur. Vast increases in Web traffic were measured during the Iowa Caucuses in January, when Howard Dean’s infamous “scream” became a top download. Other top-blogged events include the beheading of American civilian Nicholas Berg in May; the Democratic and Republican political conventions in July and August, respectively; the Kryptonite lock controversy in September; and most recently, on Election Day, November 2, when political blogs averaged roughly a 130 to 200 percent increase in traffic, according to data supplied by comScore.

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Finally, the demographics of blog authorship are somewhat disputed, but the bulk of bloggers clearly are within the under-30 demographic. According to a Perseus study, over 90 percent of blogs are authored by people between the ages of 13 and 29, with 51.5 percent between the ages of 13 and 19.

Blog Demographics
Age Range Blogs Created
by Age
10-12 55,500 1.3%
13-19 2,120,000 51.5%
20-29 1,630,000 39.6%
30-39 241,000 5.8%
40-49 41,700 1.0%
50-59 18,500 0.4%
60-69 13,900 0.3%
Total 4,120,000 100%
Source: Perseus Development Corp.

A more dated survey, authored by Fernanda Viegas for the MIT Media Lab, estimated 46.3 percent of blogs are started by people between the ages of 21 and 30, with 28.2 percent authored by people in the 31- to 40-year-old demographic.

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