
ETF vs Mutual Fund: Which Is Better for Beginners? Explore costs, tax implications, and trading flexibility for informed investment decisions.
Work out how much to invest each month to hit a target. Enter your goal, current savings, expected return and timeline, then press Calculate to see the deposit you need.
Written by TopicDrill Editorial Team·Updated June 2026
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The tool runs the math in two parts. First it projects your existing savings forward at the return you expect, so any head start is credited. Then it figures out the steady monthly deposit that, once compounded, closes the remaining gap to your target by the deadline you set.
The chart traces your balance climbing toward the dashed goal line. Early on the curve is gentle, but it steepens as compounding kicks in, which is why the final stretch often grows faster than the years before it.
Say you want 100,000 dollars in 10 years, already hold 10,000 dollars, and expect a 7 percent return. The starting balance grows to roughly 20,000 dollars on its own, so your monthly deposits only need to cover the rest. The calculator finds that around 460 dollars a month gets you there, with growth supplying the difference.
Returns are never guaranteed, so revisit the plan yearly and adjust your deposit if markets run ahead or fall behind. Inflation also chips away at a fixed target, a point explained at Investor.gov. To see what a chosen monthly deposit grows into instead, try our future value calculator.
It first grows your current balance forward at the expected return to see how much it covers on its own. Whatever gap remains to the goal is filled by monthly deposits, and the tool inverts the future value of an annuity formula to find the exact deposit needed.
Use a rate that matches the type of account. A diversified stock portfolio has historically returned roughly 6 to 8 percent a year before inflation over long periods, while a savings account or bond fund will be much lower. A conservative assumption leaves more margin if markets underperform.
Because compounding does more of the work. The longer your money is invested, the more growth it earns, so you need to add less of your own cash each month. Starting earlier is the single most powerful lever for reaching a goal comfortably.
If your starting balance grows past the target on its own within the time frame, the calculator shows a required monthly contribution of zero. You are already on track and any extra deposits simply build a cushion beyond the goal.

ETF vs Mutual Fund: Which Is Better for Beginners? Explore costs, tax implications, and trading flexibility for informed investment decisions.

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