Tinder: Dating app keeping score on users' 'desirability' quotient

Tinder, the controversial but popular dating app, is reported to be keeping score each time you swipe left and right. The match-making company took over two months to develop a complicated algorithm which assigns an internal rating to the most and least desirable people using the service. The scores are not available to the public.

The revelation was made by Tinder CEO Sean Rad to Fast Company where he said that the rating is technically not a measure of attractiveness, but a measure of desirability as it is not determined simply by one's profile photo. "It's not just how many people swipe right on you. It's very complicated. It took us two and a half months just to build the algorithm because a lot of factors go into it."

The rating, known as 'Elo score', allows Tinder to rank the most desirable users on the service by calculating not just the number of swipes but also other things a profile built, types of photos, number of photos and profile descriptions.

"This Elo score isn't a universal attractiveness though," says Tinder data engineer Tor Solli-Nowlan. "People are really polarised on even just a photographic level. While some people really favour facial hair, some do not. Same thing with tattoos, photos with pets or children, excessive outdoors shots, or photos of you with a tiger. In that sense, a photo showing you skydiving may be alluring (or not) for different reasons; some may like that you're an adventurous thrill seeker, while some might simply be intrigued by how you look."

While it is not unusual for app-driven services to provide user ratings, such a ranking on a personal level may never be available to the public. A social media app last year called Peeple received widespread backlash after it gave users the chance to review and rate anyone you meet. The branding of people as products and services outraged people so much that its co-founder Julia Cordray was targeted by online hacking group Anonymous who publicised her address.