girl math

Girl math is a joking way of justifying purchases with creative logic: if it’s under $5 it’s basically free, a return is “making money,” and a trip you paid for months ago doesn’t count anymore.

What girl math means

It’s a parody of the mental gymnastics people use to feel better about spending. Fortune summed up some classic rules: anything under $5 is basically free, returning something means you earned money, and a vacation paid for months ago is practically free by the time you go. The fun is in how confidently illogical it is.

It quickly got a male counterpart. “Boy math” started on Twitter/X in mid-August 2023 and mostly made fun of men’s habits, like rounding 5’9” up to six feet.

Examples

• “The concert was $200 but I’ll see it for three hours, so that’s like $1 a minute. Girl math.”
• “I returned the jeans, so the new shoes were free. That’s girl math.”
• “Girl math says if I bought it on sale, I saved money.”

Where it came from

Sources disagree on the exact start. Fortune credits the hosts of the New Zealand radio show Fletch, Vaughan & Hayley, who used it in July 2023 during a segment about a caller’s Taylor Swift tickets. The Guardian says the trend began with a TikTok by Samantha James, and Know Your Meme dates her girl math video to August 2, 2023. Either way, #girlmath had passed 45 million views by mid-August, according to Fortune, and the Guardian put it at more than 488 million by late September.

Is girl math sexist?

Some people think so. Finance creator Haley Sacks, quoted by Fortune, called it a tired, dangerous narrative that infantilizes women, and Guardian commenters argued it reinforced old stereotypes about women and money. Fortune also pointed to a 2023 Deloitte report finding men were just as likely to splurge as women, and spent more when they did. Most people using it, though, are laughing at themselves.

Related terms

• Girl dinner: a low-effort snack plate meal.
• Doom spending: spending to cope with stress.
• Loud budgeting: openly saying no to spending.
• De-influencing: talking people out of buying things.

See more terms like this in our TikTok slang guide.