Swipe dating app Tinder is showing a bias against older men, according to a new study.

Australian consumer group Choice made the discovery during a ‘mystery shopper’ investigation, which saw 60 volunteers of different demographics sign up for Tinder’s free service and then compare how much they would be charged to upgrade.

According to Australian network ABC, the results showed a striking different between the charges with gay women under the age of 30 offered an upgrade at AU$6.99/m ($5.00 US).

Meanwhile, at the other end of the spectrum, straight males over the age over 50 are charged an eye-watering AU$34.37 ($24.60 US).

As a rule, the older you are, the more ex, with under-30s consistently charged less than over-30s.

Choice’s Erin Turner told ABC: “Nowhere on Tinder’s website, privacy policy, or in its terms and conditions does the company say that it will charge you a different price based on your personal data,”

The biggest concern is that, so far, there doesn’t seem to be any kind of logic to the way prices are worked out – even within identical demographics, suggesting that the site is somehow “curating” its paid membership.

This isn’t even the first time Tinder has found itself in this position – last year, Tinder settled a $17.3 million lawsuit in California that accused the company of age discrimination through its pricing structures for users above the age of 30.

If there has been a change since then, it doesn’t seem to have been towards reducing the charging disparity – there are now just extra factors that can go for or against you, which isn’t addressing the issue.

Last year, Tinder added new gender and orientation options in response to public pressure. Choice is calling for more transparency in terms of how the fees are charted based on individual factors.

When we approached Tinder about this matter, the response was:

“Tinder is free to use and the vast majority of our members enjoy our app without upgrading to the paid experience. However, we do offer a variety of subscription options and paid a la carte features designed to help our members stand out and match with new people more efficiently.  Tinder operates a global business and our pricing varies by a number of factors. We frequently offer promotional rates – which can vary based on region, length of subscription, bundle size and more.  We also regularly test new features and payment options.”

That’s a lot of words, but none of them suggest a change to the way pricing works on the dating app.

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