About the savings calculator
Saving a little every month adds up, thanks to deposits and compound interest working together. This calculator projects your balance with a starting amount, monthly deposits and an interest rate.
Interest is usually taxable and prices rise over time, so it also shows the balance after tax and what that balance would be worth in today’s money. The bar chart and table show the pre-tax balance for each year.
Formula
- Balance = S × (1 + i)^m + D × ((1 + i)^m − 1) ÷ i
- After tax = Balance − Interest × tax rate
- Today’s money = After tax ÷ (1 + inflation)^years
Example
$5,000 plus $200 a month at 4% compounded monthly for 5 years gives $19,364.78. Interest of $2,364.78 taxed at 20% leaves $18,891.82, which is worth about $17,110.91 in today’s money at 2% inflation.