Cash Back Rewards Calculator

How it is calculated

The tool applies one cash back rate to all your monthly card spending: monthly rewards = monthly_spend × cashback_rate ÷ 100 and annual rewards = monthly rewards × 12. Spend is the amount you put on the card in a month, and the rate is a percentage (1.5 means 1.5 cents back per currency unit). If your card pays different rates in different categories, work out a blended rate first: total rewards divided by total spend, times 100. Zero spend or a zero rate gives zero rewards. Empty or negative fields, and a rate above 100%, give no result. The figure ignores annual fees, spending caps on bonus categories, introductory offers and interest on any balance you carry, all of which change what you actually keep.

Common mistakes

• Entering the annual spend in the monthly field. The result would then be twelve times too large.
• Using the headline bonus-category rate (such as 5%) for all spending. That rate applies only to a category, often with a cap, so use a blended rate.
• Typing the rate as a fraction (0.015) instead of percent (1.5). The tool reads 0.015 as 0.015%, so the rewards come out about a hundred times too small.
• Ignoring the annual fee. A card with a fee can earn less than a free card with a lower rate at modest spending levels.
• Counting rewards while carrying a balance. Interest on an unpaid balance usually costs far more than the cash back earns, and this tool does not deduct it.