With some 27 million followers, Oprah is both popular and very active, with an 'outreach' score of eight out of ten. The talk show host, producer and all-round lifestyle guru has a media empire of her own, with her own TV network and five books, but Twitter is at the heart of it. Her Sunday morning show in the US, Super Soul Sunday, often trends on the platform.She's recently started using the live-streaming service Periscope to broadcast (or, as she calls it, PeriscOprah) what she's been up to, such as cooking Tibetan dumplings with a TV chef, but she also tweets about heavier matters like faith and race. — Oprah Winfrey (@Oprah)
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Not the highest ranking Kardashian on our list, but the most famous of reality TV's first family comes in at eighth position, with an impressive 19, 000 tweets since 2009. Kim likes to keep her fan base up-to-date, and with the maximum 'influence' score of 1, 000, are 32 million of them are highly engaged with her. Her tweets are casual updates on her life with her equally famous family - husband Kanye West and baby North.
Kanye's bday today is gonna be a major SWISH!!! I planned the craziest surprise! Will share later! Sooooo excited!
— Kim Kardashian West (@KimKardashian)
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Ellen - who has 43 million followers and the maximum 'influence' score of 1000 - entered the record books in 2014 with the most-retweeted tweet of all time. Her celebrity selfie at the Oscars has been retweeted a staggering 3.3 million times, and it wasn't a one off. Ellen's brand of frankness, humour and feminism is what earned her a place on our list.
If only Bradley's arm was longer. Best photo ever. #oscars
— Ellen DeGeneres (@TheEllenShow)
Lady Gaga is notorious for her intimate relationship with her fans. The singer often posts about meeting supporters - or her 'little monsters' - and documents her meetings with them extensively on Twitter, as well as retweeting tweets they send to her. She also promotes her tours and merchandise, and offers up backstage pictures from performances. — Lady Gaga Facts (@LGMonsterFacts)
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With only five million followers, Iggy's support base on Twitter is not as big as others in the top ten.
But, unlike Gaga and Ellen below her, the music star has the highest possible score for 'outreach', meaning she actively communicates with the followers she has. That manifests itself in her 40, 000 tweets, sent since she joined the site in 2010.She is currently using Twitter to share her current collaboration with Britney Spears - who also appears high on our list.
In case you haven't seen it yet...the #PrettyGirlsMusicVideo is out now! @britneyspears
— IGGY AZALEA (@IGGYAZALEA)
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Bella Thorne has long been a star on US TV in shows like Disney Channel's show 'Shake It Up' and a Gap advert when she was tiny. The actress recently spoke to Cosmopolitan magazine about dealing with social media 'haters' abusing her (she has six million followers). "You take pictures with a guy and you're a ho; you take pictures with a girlfriend and you're a lesbian, " Thorne said. "I don't understand how girls can sit there and pick one another apart. My friends and I don't do that." She has also taken part in social media campaigns like the National Day to Prevent Teen Pregnancy in the US, posing with high school children with the event's hashtag.
Monday. Have a good one 💤💤💤💤👊
— bella thorne (@bellathorne)
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Placing at number four, Kim's 30-year-old younger sister has more influence than her sibling, though she has half the number of followers at 14 million. Khloé recently had a very public Twitter spat with US hip hop artist Amber Rose, who accused the Keeping Up The Kardashians star of tweeting "11 times and try to humiliate me" after Amber criticised Khloé's younger sister Kylie for starting a relationship with a married man.
Your actions and your words should always agree with each other. Don't say one thing, then do another.
— Khloé (@khloekardashian)
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Nicki Minaj is prolific. As with a lot of other music stars, many of her tweets are retweets of her followers, boosting her 'outreach' score and no doubt endears her further to her 19 million fans. She retweets pictures of herself, adoring comments, and even, recently, someone's birthday cake which had a picture of her face on it. She takes the strong position of third in our league table thanks to her 34 thousand tweets which keep people up to date on exactly where she is, what she's up to and what music she is working on.
— NICKI MINAJ (@NICKIMINAJ)
Just missing out on the top spot is Ariana Grande, another singer. At only 21, Ariana has a devoted following after releasing her first album in 2013 and being showered with awards. Ariana's popularity is also boosted by her use of Twitter as a platform to denounce gender inequality and sexism. Angry at how media coverage often mentions her in the context of her boyfriend, musician Big Sean, she issued what Vanity Fair called a feminist "sermon" on the social network, which drew 78, 000 retweets and praise from many corners. — Ariana Grande (@ArianaGrande)
- 1 Gabe Ginsberg via Getty Images
The woman who wields the most power
in our ranking - perhaps surprisingly, given she's not as present in the limelight as she used to be - is Britney Spears, whose two-decade career and 'ordinary' family pictures means she has an army of 42 million followers who are furiously active in reading and sharing her posts. The all-American singer is officially the most influential woman on Twitter. Her Hit Me Baby One More Time days may be gone, but Britney is now performing a residency in Vegas, and duetting with number five on the list, Iggy Azalea. With both the maximum 'influence' score and the maximum 'outreach' score possible, Britney is involved with her fans - and they respond to her. What's so special about Britney on Twitter? Apart from the thrill of interacting with the woman behind an iconic 20-year pop career, her appeal could well be the "off-duty" pictures she posts with her children, revealing a casual, authentic side to one of the most recognisable stars in the world. — Britney Spears (@britneyspears)