Purchase Optimizer — Best Card for Any Purchase

Enter a purchase amount and category to find which credit card in your wallet earns the most rewards.

The Purchase Optimizer tells you which card in your wallet earns the most on a specific purchase. Enter the amount and category — groceries, dining, gas, travel, and more — and it ranks your cards by real return: the earn rate multiplied by how much each point or mile is actually worth, so you never leave rewards on the table.

How it works

  1. Pick the spending category and enter the purchase amount.
  2. The tool applies each card's earn rate for that category (for example 4x on dining, 3% on groceries, 1x on everything else).
  3. It converts points and miles to a conservative cash value, so a points card and a cash-back card compare on the same scale.
  4. You get a ranked list of the single best card to use for that exact purchase.

Illustrative: a $300 grocery run

Card typeRateValue returned
Card earning 4x points on groceries1,200 pointsabout $18 at 1.5 cents/point
Card earning 3% cash back on groceries3%$9.00
Flat 2% card2%$6.00

Figures are illustrative to show the method; your result uses your cards' actual rates.

Common questions

How does the Purchase Optimizer decide the best card?

It multiplies each card's category earn rate by a conservative cash value per point or mile, then ranks by the dollar value returned on your purchase amount.

Does it account for points being worth more than cash back?

Yes. Transferable points are valued using conservative per-point estimates, so a strong points card can beat a flat cash-back card even at the same multiplier.

Do I need to enter my real cards to use it?

No signup is required — you can compare across popular cards, and the ranking is based on published category earn rates.

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