Tinder knows how desirable you are (but it won't tell you)

If the people you're matching with on Tinder aren't quite as attractive as you would like, it turns out there's a reason for it: the app creates an internal "desirability" score and uses that to pair people.

The internal scores, called Elo scores, after the chess term used to rank players' skills, were revealed by Fast Company, when one of its journalists was allowed to see their rating. For those that want to know how they rank, however, the scores are secret and there's no intention to make them public.

Tinder, which has more than 50 million users, claims that its matches aren't just based on how attractive a person is. The company says as there's more than just photos on a person's profile and not all right swipes are based on these (although, if we're honest with ourselves most swipes are based on how someone looks).

"It’s not just how many people swipe right on you," Tinder CEO Sean Rad told Fast Co. "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."

Tinder isn't the first company to have built internal ratings for its users. In much the same way that customers can rate their Uber drivers, drivers also rate their passengers. On Uber it is possible to request to see an average rating.

The company didn't provide many details on how its algorithm works but it is likely it is based on information included on a user's profile. It's possible that the more details -- education, the number of photos on a profile, how much the app is used -- are taken into account when the score is worked out.

As such Rad says they are "desirability" scores rather than attractiveness.

However, a large part of the scores are likely to be based on swipes as it is the most common interaction on Tinder. The company has previously said that 10 billion matches have been made on the app, which will have produced a huge amount of data about the desirability of everyone on the service.

Tinder data engineer Tor Solli-Nowlan said: "Every swipe is in a way casting a vote: I find this person more desirable than this person, whatever motivated you to swipe right. It might be because of attractiveness, or it might be because they had a really good profile."

This article was originally published by WIRED UK