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What is "girl math?" The TikTok trend redefinining bad budgeting

What is "girl math?" The TikTok trend redefinining bad budgeting
What is "girl math?" The TikTok trend redefinining bad budgeting 03:52

BALTIMORE -- A new personal finance trend has TikTok users recommending humorous new ways to rethink their spending habits.

We've all justified unnecessary purchases before, but now social media has labeled the habit as "girl math."

So, what exactly is it?

You may have seen the videos popping up online, or maybe you do a bit of girl math yourself.

Let's add it up. In the world of girl math, cash is not real money, buying on sale is a form of saving, and cosmetic procedures is an "investment in your future self." 


Girl. Math. @shsu.chicks (via:mckennaelianna/ig)

♬ original sound - Chicks

While this isn't exactly a new way of thinking, New Zealand radio show Fletch, Vaughan & Hayley have essentially coined the term. 

"We did a bit of girl math. Carmen wanted to get hair done and Shannon was like... Shannon girl mathed her and worked out how basically she's getting it for free"


#girlmath with an Economics Expert 🫢 Let us know if you help justifying your spending 🤪 #basicallyfree

♬ original sound - FVHZM

Another popular "girl math" concept is that going to a concert is basically free because you purchased tickets so long ago it doesn't really count. 

It's all meant to be funny - simply bad math used to justify purchases and spending habits. 

It also promotes the stereotype that women are not good at math, and therefore not good with money. 

"It seems a little, you know, condescending and misogynistic," said J.P. Krahel, a professor of accounting at Loyola University Maryland. 

We all do it from time to time, not just girls. It's boys, men and women. 

"I didn't spend any money today... what happens to my budget tomorrow?" One girl math TikTok asks. "My budget is doubled! There we go." 

So, is the personal finance trend really helping anyone? 

"Girl math is a bit of an in-joke," Krahel said. "The idea is you, you kind of twist reality a bit. And again, this is all very tongue in cheek, but you act like you're saving money when you're not."

Experts say there is a helpful financial rule for "good math" we can follow: the 50-30-20 rule. 

The rule means 50% of your budget should go towards those firm costs like rent or mortgage, insurance, car payments and food. Then 30% is for extra spending on non-essentials like eating out or other activities.

And 20% goes straight to savings or debt repayment.

"If somebody has a budgeting problem, girl math is not going to save them," Krahel said. "If somebody doesn't have a budgeting problem, girl math isn't going to hurt them. It's just it's the best form - it's just a way to have fun with money."

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