Cash Back Calculator
Enter your monthly or annual spending by category (groceries, dining, gas, travel, everything else), the cash back percentages your card pays in each, plus any annual fee, and the calculator returns net annual rewards. Compare up to four cards side-by-side to see which actually pays more for your real spending pattern — the 5% category card often wins on paper and loses once fees are factored in.
How cash back is calculated
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1
Enter your spending by category
Monthly is often easiest; the tool multiplies by 12. Include groceries, gas, dining, travel, streaming, and catch-all "everything else".
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2
Enter each card's cash back rates
Per category and the base rate for anything uncategorised. Respect quarterly caps if the card rotates categories.
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3
Subtract annual fee
Net rewards = gross cash back − annual fee. Welcome bonuses can be amortised over year one.
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4
Compare cards
Side-by-side table shows gross rewards, annual fee, net return, and effective overall cash-back percentage on your total spend.
Card types by reward structure
| Type | Example | When it wins |
|---|---|---|
| Flat-rate (e.g. 2% on everything) | Citi Double Cash | Simplicity; high unclassifiable spending |
| Tiered (e.g. 3% groceries, 2% gas, 1% else) | Blue Cash Preferred | Heavy grocery/dining spenders |
| Rotating 5% categories | Chase Freedom Flex, Discover It | Engaged users who activate quarterly |
| Premium travel | Chase Sapphire Preferred | Frequent travellers who book through issuer portals |
| Pay-for-category | Bank of America Customized Cash | Spending concentrated in one chosen bucket |
Hidden costs beyond annual fee
- Foreign transaction fees (2-3%) wipe out cash back on overseas spend. Many premium cards waive these.
- Interest: any month you carry a balance, interest exceeds lifetime rewards at typical 20%+ APRs.
- Missed statement dates for 0% intro offers: deferred interest retroactively applied.
- Cash advances: 3-5% fee upfront plus interest from day one. Never a cash back category.
Welcome bonuses
Most cards pay $150-$750 as a sign-up bonus after spending $500-$4,000 in 3 months. This often dwarfs category cash back in year one. When comparing, amortise:
- $200 bonus ÷ 12 months = $16.67 extra monthly cash back (year-one only)
- $500 bonus on a $95-fee card = net $405 first year
Real-world pattern: the two-card stack
Many cash back optimisers run two cards:
- A 5%/3% category card for groceries/dining/gas
- A flat 2% catch-all card for everything else
This beats any single card for spending concentrated in premium categories while the flat card covers tails. The calculator supports this — just enter both cards and assign spending to each.
Watch the caps
- Rotating 5% categories often cap the bonus at a few hundred dollars of spend per quarter (e.g. a $1,500 quarterly cap = $75 max), then drop to 1% above that.
- Tiered grocery cards typically cap the elevated rate at a few thousand dollars of annual spend, after which it falls to the base rate.
- Hit the cap → shift spending to another card for the remainder of the period.
Exact rates and caps change and vary by issuer — always verify the current terms with the card issuer before relying on them.
Don’t over-optimise
Saving $50/year of cash back by juggling five cards is often not worth the cognitive overhead or the risk of missing a payment. Two cards is the sweet spot for most people.
Frequently Asked Questions
In the US, rewards on personal credit cards are treated as rebates, not income, so they’re not taxable. Business card rewards can be different — consult a tax professional.
Not always. A 5% card with a $95 annual fee needs significant category spending to beat a no-fee 2% card. The calculator does this math for your actual budget.
Sometimes. Transferable points (Chase UR, Amex MR) redeemed for specific travel can be worth 1.5-2 cents each; standard redemption is 1 cent. If you don’t maximise transfers, straight cash back is simpler.
Optionally. Toggle “include year-one bonus” to factor in sign-up rewards. Leave off for steady-state year-two-plus comparison.
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