Round-Up Savings Calculator

How it is calculated

The tool uses plain multiplication with no interest. monthly saved = transactions_per_month × avg_roundup and total saved = monthly saved × months. It also counts the purchases involved: transactions = transactions_per_month × months. The average round-up is the money per purchase that goes into savings: a purchase of 3.55 rounded up to 4.00 contributes 0.45. Because rounding goes to the next whole dollar, the average cannot be above 1, and a value such as 1.2 shows no result. Transactions per month and months must be whole numbers; 60.5 transactions or 1.5 months give no result. Zero in any field is accepted, and negative or empty fields give no result. Because there is no growth, the result is only what you deposit, not what the savings account might add.

Common mistakes

• Entering the total spent per month instead of the number of purchases. The first field is a count of transactions, such as 60, not a money amount.
• Entering the full purchase price as the round-up. Only the difference up to the next whole dollar is saved, so each round-up is at most 1 and anything higher shows no result.
• Counting transactions that are already whole amounts without adjusting. A purchase of exactly 12.00 has no round-up, so include it in the average as zero.
• Putting a 2x or 5x round-up multiplier into the average. If your app doubles the round-up, the average can pass 1 and the tool shows no result, so model such a setting by doubling the monthly result instead.
• Assuming it shows interest. The figure is deposits only, so it will understate the balance in an interest-bearing account.