In general, your score would immediately go down as your credit utilization would go up (outstanding balance over total available credit).
0/infinity is still zero
Re:How Equifax Became a Private IRS
by sixstringtheory on Monday January 23, 2023 @10:47PM
(#34498930)
…depending on the languages used in their backend and the quality of their development efforts…
The balances are instantaneous balances, not ones that are being financed. So, if you use and pay off your card every month (as makes sense to me for points/cash back, ease of chargeback, and convenience), then your numerator won't be zero on most days. (For me, it's not $0 on any days, because of the timing of statements.)
Re:How Equifax Became a Private IRS
by medvezhenok on Tuesday January 24, 2023 @09:02AM
(#34503621)
You could theoretically pay off the card before the statement posts to keep the balance at zero. Usually not worth it, but if you want to boost your credit score before getting a mortgage, that trick usually works.
In general, credit scores are optimized for the average consumer - and so behaviors around the edges don't always make sense in terms of your score going up or down. If you think about the system that was replaced by credit cards (i.e. keeping a tab open with many different stores), you'd be hard pressed to say that the amount of credit extended is lower now (overall), than under the old system. Whether that's a good thing or not is a different question.