Twitter’s IPO S-1 document states they have 215m monthly active users (MAUs). At p. 46 of their S-1, they admit there is no independent confirmation of this number.

The real number is much lower.

What does Twitter mean by “accounts”? Twitter looks at active accounts. This includes:

  • Humans: A person logs into Twitter to read messages or send a message.
  • Multiple accounts: Many people use several accounts. For example, someone may have two accounts for personal and work use. A company team may have 10-20 accounts for different purposes (an account for each product, each service, the company, the CEO, the company dog, and so on). Large corporations may have thousands of accounts.
  • Robots: many computers log into Twitter to collect messages or send messages. For example, weather reports are automatically sent.
  • Automated activity: Your cell phone automatically checks Twitter every few minutes for new messages. These automated checks are considered as activity, so the user is counted as an active user. Someone may have set up Twitter on her phone four years ago and forgot about it, yet she’s still considered a daily active user.
  • Spammers: Marketing and spammers use millions of fake accounts to send messages and spam.

All of these are considered active accounts.

A better way is to see how many humans use Twitter. This can be done by polls. The Pew Internet and American Life Project ( find 16% of US adults (20-75 years old) use Twitter. There are about 250m adults in the USA, so that’s 40m adult Americans on Twitter.

Pew also finds 24% of US teenagers use Twitter (May 2013). There are 30m US teenagers (age 13-19), many of whom had a party next door last night (including Ane and Ingeborg). So that’s 7.2m teens on Twitter.

This means there are 47.2m people in the USA on Twitter in mid-2013.

Twitter told me 77% of their users are outside the USA. If 47.2m are in the USA, then I estimate an additional 128m people outside the USA for a total of 175m people. That leaves about 40 million extra accounts which are multiple accounts, robot accounts, or spam accounts.

Mike Isaac at AllThingsDigital wrote Twitter has had over a billion registrations, which means the abandonment rate is greater than 83%.

Why do people sign up but not use Twitter? Twitter won’t give a clear reason on how to use it. The interface is also primitive and confusing. Furthermore, Twitter encourages the idea that Twitter is for celebrities, so everyone else has little incentive to use it.

Twitter’s presence is greater than its use. TV shows, billboards, and advertising now show hashtags and tweets. A study by Edison Research and Arbitron shows that 44% of Americans see tweets daily through other media.

Revenues for 2013 will be around US $750m. It’s roughly doubling every six months at the moment, and revenues for the first half of 2013 were $253.6m, so I’m guessing $500m for the second half with a total of $750-800m for the year. Some of it (13%) comes from fees for access to data. The rest comes from advertising (75% in the USA).

Be careful with data from 2012 or earlier. Numbers have changed substantially in the last twelve months. In 2011, only 12% of teens used Twitter. 26% of teens are now on Twitter (Sept. 2013).

Researchers estimate 3% of accounts are fake (around 5 million accounts). Twitter themselves say about 5% (11m) are fake. (Yes, I’ve read estimates of 10-20%, but I think these lower numbers are better justified.)

There are 500m tweets per day (October 2013). (Remember, many are automated or spam.)

Documentation for these numbers is in my book #TwitterBook. See the References section or on the book’s webpage at The book is a free download this week. Next week, it goes on Amazon for $10.

If you have a better way to calculate Twitter’s numbers, please let me know.