DigitalSo, How Many People are Actually on Twitter?By Lauren Dugan|March 24, 2011 ShareBy Lauren Dugan|March 24, 2011 Share Twitter has been nototiously tight-lipped about exactly how many of its 100s of millions of accounts are active. They, understandably, don’t want it to get out that only a small percent of Twitter accounts are actually being used by real people. New data from eMarketer sheds some insight on the true number of active Twitter users – and it’s probably smaller than you think. Earlier last year, Pew Internet and American Life Project released some demographic information about Twitter users, and found that about 8% of American Internet users were on Twitter.The new report by eMarketer comes up with similar numbers.The firm estimates that 20.6 million US adults will access Twitter at least once a month this year. This is up about 26% from the 16.4 million who accessed Twitter monthly last year.eMarketer also predicts that by 2013, about 28 million US adults will be on Twitter, actively using it at least once a month.According to the US Census Bureau, the current population of the United States is about 311,000,000. This means that, according to the numbers from eMarketer, about 6.6% of the population uses Twitter. However, the percentage of adult population on Twitter would be higher, likely around the 8% numbers from Pew.So what does this mean?It’s pretty clear to anyone on Twitter that it reaches just a fraction of the US population, and it certainly isn’t nearly as large as Facebook. However, if you see Twitter as a place for influencers, its still-niche status is something that adds, not detracts, from its power. It also has a significant international presence, and its diversity and global reach is part of the reason it ha become such an influential technology. Adweek Adweek