When Twitter files its S-1 papers for its IPO, it will answer a simple question that has been a bit of a mystery for observers and fans of the company: How many users are on Twitter?
It's a simple question without a simple answer right now.
The company recently wrote a blog post saying it had 200 million users. All Things D believes it has 240 million users. Venture Beat says it has 1 billion users. And where do the 40 million users of Vine, Twitter's mini-video sharing app, fit in?
Part of the confusion here is that these reports are likely mixing up different technical terms for users. There is a difference between the total number of registered user accounts on Twitter — the entire Twitter universe — and the more meaningful numbers of monthly active users and daily active users.
But even so, Twitter executives will be anxious about the public and investor reaction to its S-1 when it gives some solid historic numbers about its user base.
The biggest, most difficult problem for Twitter is its notorious population of fake or abusive user accounts. Fake accounts are set up by companies who sell new followers to advertisers who want to build large follower populations quickly. They tend to consist of "empty" accounts or bots which are mostly inactive, or programmed to auto-retweet other accounts. Twitter CEO Dick Costolo has made his anger clear at "bulk" follower providers.
Back in April, Twitter's fake user population was estimated at 20 million accounts out of a total of 500 million. But Twitter spokesperson Jim Prosser also said at the time that 40% of Twitter accounts appear to be inactive because many people set up their accounts simply to "listen" to other people, rather than tweet themselves.
The IPO filing will likely give Twitter's total registered user base, and its monthly active users. If it follows Facebook's example, it will also give an estimate of the number of fake or abusive accounts. Although there was a lot of controversy over Facebook's fake account total, it generally hovered around only 5% of users. And because it's easier to "know" who someone really is on Facebook, it's easier for users to weed out fakes from their friends. On Twitter, where people use nicknames and handles that give no clue to their real identity, weeding out fakes is a lot harder.
On My Twitter account, about 4% of my followers are fake, and 13% are inactive, according to Status People, a web site that measures fake Twitter accounts. That's 17% of my 4,500 followers who are basically useless to advertisers and next to impossible to monetize for Twitter. (And I have no idea who they are.)
So once investors have whittled away the fake and inactive accounts from Twitter's user base, in order to calculate a meaningful average revenue-per-user, they're likely going to find that Twitter is a lot small than Facebook.
In terms of growth, that will be a good thing — Twitter is a huge success based on a smaller base, and has room to amp up that growth. But it may also explain one of Twitter's stranger phenomena: That while hardcore users — people in the media and tech worlds, mostly — love it, the vast majority of ordinary people still shrug when they encounter it.
We emailed Twitter for comment and we'll update this is the company responds.
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