Future value of a lump sum plus regular monthly contributions. Results update as you type.
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Results are estimates for education only and are not financial advice. Returns are not guaranteed and vary year to year in real markets.
Each monthly contribution is added at the end of the month, then earns the monthly share of the annual return from the next month on. The yearly table shows the balance at each year end.
FV = P × (1 + r)^n + PMT × (((1 + r)^n − 1) ÷ r). Here FV is the future value, P is the initial investment, PMT is the monthly contribution, r is the monthly return (annual return ÷ 12), and n is the total number of months. Contributions are added at the end of each month.
An initial investment of $50,000 plus $500 contributed at the end of each month, at a 7% expected annual return for 25 years, grows to $691,306.76. You put in $200,000 in total, so earnings are $491,306.76.
No, it is a nominal return before inflation. If prices rise 2% a year while your investment returns 7%, your real purchasing power grows by roughly 5% a year. To plan in today's dollars, run the calculation with a return reduced by expected inflation.
Real returns bounce around, so the result is an estimate, not a promise. A constant return gives the middle of the range: good years push the final value above it and bad years pull it below. The yearly table shows the path only under the steady assumption.
Use this calculator whenever the question is what a sum of money grows to, rather than what a loan costs. It fits retirement saving, education funds, and general investing. Enter a starting amount, a monthly contribution, an expected annual return, and a number of years. The page model adds each monthly contribution at the end of the month and compounds the annual return monthly. The result separates your own contributions from the earnings, so you can see how much of the final number is growth and how much is money you put in.
A starting amount and a monthly habit play different roles. Take $10,000 to start, plus $200 at the end of each month, at 6 percent for 30 years. The final balance is $261,128.76, from $82,000 contributed and $179,128.76 of earnings. The $10,000 alone would grow to $60,225.75. The $200 monthly contributions alone, $72,000 in total, would grow to $200,903.01. In this example the monthly habit contributes more to the outcome than the starting amount, because $72,000 of contributions beats $10,000 of starting money even though the starting money has longer to compound. When the starting amount is large, the balance tips the other way, which is why the calculator shows both parts separately.
The return assumption matters more than any other input, so test more than one. The same $10,000 plus $200 a month for 30 years gives $211,129.17 at 5 percent and $325,159.17 at 7 percent, a difference of $114,030.00 from a 2 point change in return. That spread is the reason to plan around the lower number: if the plan only works at an optimistic return, it needs a bigger contribution or a longer horizon. Also remember the result is nominal, before inflation. If prices rise 2 percent a year while your investment returns 7 percent, your purchasing power grows by roughly 5 percent a year. To plan in today's dollars, run the calculation with a return reduced by expected inflation.
Three mistakes weaken most plans. First, people use one optimistic return for every year. Real returns vary, and a single bad stretch early on changes the outcome, so test at least two returns. Second, people forget inflation, taxes, and fees. A 7 percent return before those costs is not a 7 percent return in your pocket. Third, people wait for the right moment to start. Timing the market is hard even for professionals, while a monthly contribution keeps money going in during market drops, when each contribution buys more. Starting small now usually beats waiting to start big later.
On pure math, a lump sum usually wins, because it gets more time to compound. On behavior, a monthly plan usually wins, because it turns saving into a routine and avoids the risk of investing everything just before a drop. Most people do best with both: invest what you already have, then keep a monthly contribution going. The calculator can show each part, so run both and compare.
Use a cautious one and test two. Many plans use 5 to 7 percent for a diversified portfolio before inflation, but the right number depends on what you hold. Cash and bonds earn less than stocks on average and vary less. Never treat the result as a promise: past returns do not guarantee future returns, and the page states this in its disclaimer.
No. The result is a nominal balance before tax, fund fees, and account charges. In a taxable account, yearly tax on dividends and eventual tax on gains reduce the outcome. In a tax advantaged account, the tax treatment depends on the account type. To allow for costs, run the calculation at a slightly lower return.
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