Compound growth calculator

How this calculator works

This calculator grows your money one month at a time. Each month, the balance earns one twelfth of the yearly return you enter, and then your monthly contribution is added. It repeats for every month in the years you choose. The projected balance is the result. Your contributions are the starting amount plus every monthly deposit, and growth is the balance minus those contributions. The chart shows the balance at the end of each year.

Assumptions: the return is the same every year and compounds monthly. Real investments go up and down, and savings account yields change, so the return you enter is an assumption, not a promise. Contributions are made at the end of each month and never change. Taxes, fees and inflation are not included, so the balance is in future dollars before those costs.

How this affects buying a home: savings in bank and investment accounts can go toward a down payment and closing costs, or count as reserves after closing. Lenders usually ask for recent statements and may count only part of the value of stocks or retirement accounts, since prices can fall. Some programs, sometimes called asset depletion loans, can use large savings to help qualify when regular income is modest.

Example: enter a $10,000 starting amount, $300 a month, the return you want to test, and 10 years. Then change the years to see how time affects the growth share.

Related: Retirement projection calculator · Down payment goal planner · Asset depletion loans