The ultimate girl math guide – how to justify buying what you want

15 November, 2023 / words by Cloe Vaz-Wiggins

If you are an avid TikTok-er then you would have heard of the latest ‘Girl Math’ trend. It’s a pretty fun and humorous one whereby women explain and justify their purchases by ‘Girl Math’.

Where did it all start?

It appears that this trend began when clips were shared of New Zealand radio show, Fletch, Vaughan & Hayley. Callers share the price of a big purchase i.e. $656 for a bedding set or $1,000 on a luxury bag, with the hosts helping the caller to justify the price by breaking it down. For example, using the bedding set for 365 a year and splitting the cost per night between two, as you share the bed with a partner. This makes the bed set just $0.90 a night which is a lot more justifiable than the $656. If anything, this makes the purchase ‘almost free’.

As with everything on TikTok, the idea caught on and got people sharing their own examples of the some-might-say-delusional logic.

Tell me more

Though initially, it began for just big, impulse purchases, the logic can be applied to all types of purchases. For example, if you have booked and paid for a concert a year in advance when you attend the concert it is free. 

It can apply in so many ways … If you return clothes after you have bought them, the money that gets refunded back to you is income, which can then be further spent on more clothes. Any money spent inside the airport or outside of the country you reside in “free”. 

Try to work backwards and figure the cost per unit or the cost per use. So, if you are buying an outfit, divide the price by the number of times it will be worn. In this scenario you can even look deeper and suggest that if you opt for a dress rather than a top and trousers, you are saving half of the expense as you can get just one item as opposed to two.

No wonder everyone is loving this trend… It’s a simple way to make you feel good and empowered about your purchases. Some people are even saying it makes them feel like they’re making money! We have all been there, we all need a little boost sometimes to justify things.

In one video, an explainer describes how cash is not real money so buying things with cash makes it free. Take from this what you want but most importantly, cash is cash and though that electronic trail that is left when using cards is not present, it is still a transaction.

It should also be said that though it’s ‘Girl’ Math it can apply to men! As with most things taking the internet by storm at the moment, the focus is on women – like girl dinner, hot girl walk etc. But of course, this is not exclusive. In fact, applying the trend to just women can impact quite negatively on society by bringing unrealistic stereotypes that women are not good at math nor are they good with money/spending. So, men, if you are also feeling this vibe, ride it through. You can also get involved with Girl Math!

Word of warning

This trend is supposed to be humorous, and it should be clear that justifying the purchases and them feeling free does not mean they are.

It can bring negative consequences to your bank account if it is used too much. If you are using the trend too deeply that you are seeing it as legit and not playful then this indicates you have got past the point of it and the fun sense of Girl Math is lost. So just make sure you are clear…are you applying Girl Math for the right reasons? Know the intention of your purchase and don’t get trapped.

Have you jumped in on the trend yet? How will you apply Girl Math?

In respect of the information above, this content is only for informational purposes and does not constitute any kind of financial advice.


Cloe Vaz-Wiggins


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