Why is the right card so hard to pick at checkout?
Every card carries its own bonus map. Groceries might earn 4x on one card and 1x on another, and issuers do not surface any of this at the register. A $180 grocery run at 1x instead of 4x compounds into real money over a year.
How does Best Card work?
CardStack loads your wallet and compares earn rates by category. Transferable points (Amex Membership Rewards, Chase Ultimate Rewards) get valued using realistic cents-per-point estimates. You see which card wins for dining, gas, travel, or everyday spend. Search by category or by location for nearby merchant hints.
Can an app catch mistakes after I swipe?
With CardStack+ and Plaid, yes. CardStack flags transactions where you earned less than your best card would have. Wrong card at Whole Foods. Reserve instead of Gold at a restaurant. You see the gap and fix the habit.
What about shopping online?
The Chrome and Safari extension shows the best card for the site you are on and can enroll Amex and Chase offers. That puts the recommendation and the offers in one place, so there is no need to check each issuer's app before checking out.
What should I do before my next purchase?
Open CardStack, tap Best Card, pick the category or merchant. Or ask Stack: "best card for this Target run?" One correct swipe per day beats a spreadsheet you never open.
Frequently asked questions
Is there an app that tells me which credit card to use?
Yes. CardStack Best Card compares your wallet by category, location, and point valuations to recommend the highest-value card for a purchase. It is available on iOS with CardStack+.
How does CardStack pick the best card?
It uses your actual cards, each card's bonus categories, context (dining, groceries, travel), and point valuations to estimate the return per dollar for your specific wallet.
Can the browser extension help at checkout?
Yes. The CardStack Chrome and Safari extension surfaces the best card while you shop online and can enroll eligible Amex and Chase offers.
What if I already swiped the wrong card?
CardStack+ analyzes transactions via Plaid and flags when you earned less than another card in your wallet would have. Over a year, those mistakes add up.
Does Ask Stack answer "which card should I use"?
Yes. Ask Stack questions like "what is my best card for dining tonight?" or "which card for gas near me?" It knows your specific wallet.