Most people swipe the same card for everything out of habit. Here's the exact three-question check that shows you where you're leaving money on the table.
Last January I sat down with my credit card statements and ran a simple calculation. How many points did I earn in 2025? Then: how many should I have earned if I'd always used the right card for each category?
The gap was $340 in real-money value. Not some theoretical "if you transfer to the right airline" stretch — just the straightforward difference between what I earned and what was sitting there waiting to be earned, with the exact cards already in my wallet.
I wasn't doing anything exotic wrong. I was just using my Chase Sapphire Reserve for groceries instead of my Amex Gold. I was using my Amex Gold for gas instead of my Costco Visa. Little habit mismatches, compounding across 12 months.
Here's the three-question audit I now do every six months. It takes about two minutes.
Pull up your credit card statements for the last 90 days. Don't overthink it — most card apps will categorize automatically. Find your top five by dollar volume. For most people it's some combination of:
Write them down in order. These are the only five categories that actually matter for optimizing your cards. Everything else is noise.
Now look at which card you've been using for each category. Look up what multiplier that card earns there. Not the card's headline number — the specific category multiplier.
A lot of people with an Amex Gold think of it as a "dining card" — and it is, at 4× on restaurants. But they forget it also earns 4× at U.S. supermarkets. Meanwhile they're using a 2% cash-back card for groceries because "it's simple." That's a 50% penalty on your second-largest spend category.
You don't need to go shopping for new cards (yet). Start with what you have. List out every card in your wallet and what it earns on each of your top 5 categories. Then build a simple cheat sheet — five categories, five cards. One card wins each row.
Tip: Take a photo of your cheat sheet and set it as your wallet's lock screen background. Sounds cheesy, works perfectly. You'll never forget to check at the register.
Let's say you spend $800/month on groceries and you're earning 1× on a flat 2% card vs. 4× with an Amex Gold (where points are worth ~1.8¢ each via Amex Travel transfers). That's:
That single category fix is worth $499/year — more than the card's $250 annual fee.
That's a different question — and a legitimate one. But start here first. Most people have 2–4 cards and are systematically misusing at least two of them. Fixing that costs nothing and takes two minutes.
Once you've cleaned up your existing setup, then it makes sense to ask whether a new card would help — because now you know exactly what gap you're filling.
The ardocards quiz shows you your best card for every category in your wallet — in about 3 minutes.
Take the quiz →Free account — takes 30 seconds.