Compound Interest Calculator
Project how your savings could grow with monthly contributions. Compound growth means earning returns on earlier growth as well as the money you put in.
Estimate your growth
Starting balance
$Monthly contribution
$Years to grow
yearsFuture value
$691,150You put in
$190,000Interest earned
$501,150Contributions
Interest earned
A worked example
Start with $10,000 and add $500 at the end of each month for 10 years. At a constant 7% nominal annual return compounded monthly, the model ends at $106,639. You contributed $70,000 in total; the rest is modeled growth before fees and taxes.
Try changing one input at a time. A larger contribution is under your control; a higher return is not. For a spending goal, compare the future balance with costs after inflation.
Frequently asked questions
Each period adds growth to the balance, so later returns apply to previous growth as well as contributions. This tool compounds monthly and adds contributions at the end of each month.
A constant 7% nominal annual return, a common long-run assumption for a diversified, stock-heavy portfolio, compounded monthly with each contribution added at the end of the month. It leaves out taxes, fees and inflation, and real returns vary year to year and are not guaranteed. The result is a scenario in future dollars, not a promised balance.