SHARE OF FOLLOWERS CANDIDATE FOLLOWERS WITH <100 TWEETS <100 FOLLOWERS THAT ARE FAKE Trump 7.58m 61% 72% 8% Clinton 5.93 62 72 7 Biden 1.16 59 66 6 Bloomberg 1.41 70 74 5 Sanders 1.94 34 52 4 Cruz 1.04 51 64 3 Kasich 0.29 43 58 2 Twitter following of 2016 candidates and almost-candidates As of April 13, 2016 Source: Followerwonk, Status People, Twitter Counter

The millions of Twitter accounts following Donald Trump include lots of questionable ones — ones with very few tweets, or few followers, or on Twitter for just a few months. Many are probably fake.

Trump has recently gotten negative attention for the poor quality of his Twitter following (which adds to lots of coverage of his occasionally racist and sexist retweets and retweeted accounts). He has used his Twitter account for free and unfiltered communication with a greater number of followers than any other candidate — but if many of them are fake, that platform would be less powerful than it appears. But @realdonaldtrump is hardly the only politician with a big Twitter following that includes many dodgy accounts. Every major candidate left in the presidential race — and two men who flirted with running but chose not to — has lots of followers that fit this bill. Trump has a greater share than most, but not much more than Democratic front-runner Hillary Clinton. Her rival, Bernie Sanders, has far fewer Twitter followers than Trump or Clinton, but those accounts that do follow Sanders appear more likely to be real and active.

There is no universally accepted definition of what a fake Twitter account is. Some egg avatars with zero followers and no tweets might be on the social network just to read news. Other accounts have a profile photo and lots of tweets and followers but are part of networks of zombie accounts tweeting spam. Status People, a social media analysis company, uses an algorithm to estimate how many follower accounts are fake, using flags such as how often a user tweets and how many accounts they follow that follow them back. Its estimate last week that 7 percent of Trump’s followers were fake was reported by The Washington Free Beacon and made the rounds on — where else — Twitter this week. (That was up to 8 percent this week.) Rob Waller, founder of Status People, didn’t respond to a request for more details about how the site defines fake followers. (Disclosure: 13 percent of FiveThirtyEight’s followers are fake, as are 18 percent of mine, according to Status People.)

Other, more objective measures of the nature of candidates’ Twitter followers square with Status People’s. Followerwonk is an app that evaluates Twitter followers by measures such as the number of accounts with fewer than 100 tweets and fewer than 100 followers. They sent us their latest data this week, and among the five Republican and Democratic candidates, Trump’s and Clinton’s followings have the highest percentage of infrequent tweeters. They also have the highest shares of followers with very few followers. Sanders’s following scores best by both these measures.