Suddenly the constant stream of selfies and #girlsquad posts makes sense - for today's models, a mammoth Instagram following equals cold, hard cash. These days, the bigger your following, the more likely you are to be booked for jobs, with models increasingly commanding a separate fee for their social media following - a fee that's often eclipsing their day rate.

But just how much the top Insta-models earn has been pure speculation - until now. According to former casting director Frank Spadafora, who runs social media monetising agency D'Marie Archive, the highest ranked supers on social - that's Kendall Jenner, Cara Delevingne and Gigi Hadid - can pull in - wait for it - up to $400,000 for a single post across Instagram, Facebook and twitter. And no, that's no typo.

Insta-cash: exactly how much Kendall, Gigi and Cara charge per post

Related story: The 21 highest paid supermodels of 2015 

Less Insta-famous, but still mega, models of Miranda Kerr and Karlie Kloss' ilk reportedly make between $35,000 and $71,000 per post. "If you want to reach a model's audience, you're going to have to pay a hefty additional fee for that," Spadafora told CR Fashion Book. "As far as commercialising a career, a girl won't get very far in 2016 if she's not socially savvy."

Jennifer Powell, head of managing social media talent for Next Models, agrees. "For sure, casting directors will ask for models with over 'X' amount of followers, and then will ask for the specs of the talent after that," she says. Next Models represents Lucky Blue Smith, who has the most valuable social following of all the male models. "It's not only valuable because of his massive Instagram numbers but because of the engagement of his audience. Most contracts want to use his social media as an advertising channel, however he's very particular with what he posts and how he connects with his audience," Powell explains. 

Insta-cash: exactly how much Kendall, Gigi and Cara charge per post

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