‘Girl math’ is pushing consumers to buy luxury. Should brands weigh in?

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Does returning an item mean you have freed up money for spending elsewhere on fashion? Is buying a Prada bag OK if you wear it 670 times at $5 a wear? Welcome to the logic of ‘girl math’, the trend sweeping social media where women justify their luxury purchases with tongue-in-cheek, faux-logical excuses.

“Girl [math] is when you’re too broke to buy a $120 sweater, so you justify it when it’s on sale for 40 per cent,” says creator @livvuli in a TikTok posted in June. “So, you pocket $50 and then you’re able to buy the $60 shirt you really like because you’re only spending $10 more than you would have if the sweater [had been] full price.” That post alone has had 3.3 million views and over 500,000 likes and is just one of thousands across TikTok and Instagram.

Many Gen Zs believe the girl math trend is a harmless bit of fun, while some brands (including Mac and Ulta Beauty) are playfully tapping its humorous potential on their own social media. However, in contrast to light-hearted TikTok trends such as ‘tomato girl summer’ or ‘showertok’, girl math has attracted criticism from a range of experts (not least in the financial advice community) who say brands should steer clear of the trend because of its irresponsible encouragement of overspending.

Along with TikTok trend ‘girl dinner’, girl math reflects a “throwing-together-to-make-ends-meet kind of energy” on social media, says Bianca Brown, senior account executive at consultancy Edelman and UK ambassador for its Gen Z Lab. “Considering what young people are up against with costs of living rising rapidly, they are desperately seeking value as well as the feeling of mobility and progression (the idea that their life is getting ‘better’), but also they are experiencing fatigue with the austerity that has trickled down from their parents. This tension demands absurd justifications for simply wanting to have nice things.”

Girl math originated on New Zealand radio station FVHZM, where morning presenters Fletch, Vaughan and Hayley launched the topic as a regular feature over the summer. Over the past month, creators across TikTok and YouTube have jumped on the trend, justifying purchasing everything from Lululemon leggings (“I did a return, so they’re basically free”) to luxury handbags.

The trend marks a shift in TikTok content, says London-based luxury fashion creator Wadzi Zoe (@wadzizoe), who specialises in luxury hauls where she’s saved money in sales or on resale to “create” more money for future purchases. “All of a sudden people are appreciating aspirational content on TikTok,” she says. “Before it had to be relatable. But now, I wonder whether because of the economy people want to watch other people spending a lot of money — or whether they want to be shown how to buy luxury better.”

Pushing Gen Z to invest in luxury

Following on from the surge of the resale market over the last five years, young consumers see fashion as an alternative asset class. And, they are questioning traditional forms of investment, with underperformance further accentuated by the impact of inflation.

For many girl math videos, the crux is cost-per-wear. Paris-based creator @databutmakeitfashion posted a chart breaking down the amount of times a consumer would need to wear a bag for it to cost $5 a wear. (You’d need to wear the average Louis Vuitton bag 2,700 times.) Girl math content has become one of the best performing posts on her channels. “OK fine I’ll buy the Dior Book Tote,” one user commented, having convinced herself through girl math that she could afford the £2,500-plus bag.

Australian musician and influencer Vials (@Vialsss), who posts girl math content regularly on TikTok, also fixates on cost-per-wear. She found a mini Marques Almeida spiked bag on Ssense. “Black goes with literally everything, so I could use this bag 40 per cent of the year,” she says in a video posted last week. “146 days, $3,85 a wear, divided by two for day and night — that’s $1.93 per evening.” The video has had over 400,000 views.

“As my interest in luxury fashion has evolved, I have reframed the way I look at spending,” Vials says. “Even though the $100 pair of shoes requires a smaller initial investment, within five years I would have to spend $2,000 or more continuously replacing the cheaper shoes. You can’t argue with girl math!”

Gen Z cares deeply about financial security, a response to unstable formative years, says Edelman’s Brown. Seven out of 10 Gen Zs want safety and security in their lives, according to Edelman’s 2021 interviews with 9,600 Gen Z aged 14-24 across China, France, Germany, Mexico, UK and the US. Some 56 per cent of Gen Z are deeply concerned about the multiple issues facing the world (including finances and security), per Edelman’s Trust Barometer 2022.

Should brands weigh in?

For many creators, girl math is no more than harmless fun. “I’m really hoping that no one’s really using girl math as a way to justify their bad spending,” Wadzi Zoe says. “I feel like we all secretly thought some of this stuff. Girl math is just a funnier way of us admitting it.”

Girl math pokes fun at how young women justify overspending, says Sarah Willersdorf, Boston Consulting Group’s global head of luxury. “While there may be some elements that ring true, our research does not suggest that young female consumers are reckless or thoughtless spenders. In fact, many of the trends you see around second-hand commerce and rental business models are anchored around notions of value and sustainability,” she says.

However, Maxine McCreadie, senior debt advisor at the UK’s largest personal insolvency provider Creditfix, has concerns. “Of course, a lot of people watch girl math videos and they take it as a bit of fun, but not everyone’s necessarily going to do that,” McCreadie says. “Brands have a duty of care to an extent. They shouldn’t push the message. If they use [girl math] as a way to justify overspending, or making slightly frivolous spending decisions, that could lead to a bigger problem.”

Some brands have weighed in. Ulta Beauty’s TikTok feed in August showed a customer in store with the caption: “When you spend $300 at Ulta Beauty but you used your ultamate rewards points so basically it’s free.” Mac Cosmetics used the trend to connect the cost-per-wear with its product usage, depicting the serotonin boost from all the compliments you’ll receive as a positive investment in mental health.

McCreadie disapproves. “This is going to sound quite dramatic, but you can get into debt in like 20 clicks,” she says. “And then, all of a sudden you’re in a shop and you’ve spent X amount of money.”

Brands should tread carefully to be sure it’s appropriate to reference ongoing social media trends. “Every week there are new things crossing our feeds — new cultural trends and memes, new formats to execute on, new channels being launched,” says Robin Sacawa, VP social strategist at Edelman. “Rather than feeling pressured to do it all, brands should be looking at individual social trends through the filters of: is there a value you can add to the conversation? Is there a POV we can share that shifts the thinking within the conversation? Is this execution going to support business objectives, or simply an opportunity to communicate with our community in a new or interesting way?”

Another concern is that girl math encourages young consumers to tap buy-now-pay-later (BNPL) services. “Free money at the time innit?” one user captioned a TikTok, discussing her use of BNPL with the hashtag #girlmath.

“We believe all consumers should have access to a safe, simple and transparent budgeting tool such as Clearpay and we encourage our customers to spend responsibly within their means,” says a spokesperson for BNPL provider Clearpay. “We advise shoppers to buy only what you can afford, reschedule repayments if needed, and use email and text message reminders to make sure your payments are made on time and you have money in your account.” As of Q1 2023, 95 per cent of all Clearpay instalments were paid on time and 98 per cent of all purchases incurred no late fees, according to the company.

BNPL is a major behavioural trend among Gen Zs (and younger millennials) that existed before girl math, says BCG’s Willersdorf. “I expect to see BNPL to continue to grow with younger consumers,” she says, “[but] most younger shoppers that I speak to look at girl math for its comical appeal, not as financial advice.”

Creators also think critics are exaggerating the dangers. “The purpose of girl math is not to encourage reckless spending and over-consumption, but to empower women to think about the long term benefits of their financial decisions,” says influencer Vials. According to a 2023 global study conducted in 23 countries by Deloitte Insights, men are statistically just as likely to splurge as women, and when men splurge, they spend almost 40 per cent more money than women.

“Many critics hyperbolise that the younger generation’s lack of wealth is caused by our spending habits, due to ‘indulging’ in lattes and avocado toast,” she says. “In reality, our generation’s economic limitations are rooted in the rising costs of living and wages that fail to keep up with inflation. According to my calculations, brunch didn’t cause a global economic collapse, babe.”

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