Estimate future investment value with compound returns and optional monthly contributions. See ending balance, contribution totals, investment growth, and yearly breakdown.
Country
Currency
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Calculate Investment Growth
Investment Inputs
Your initial lump-sum investment
Optional extra amount added each month
%
Estimated yearly investment return
yrs
How long the investment is held
type
How often returns are compounded
time
Beginning contributions receive slightly more compounding
Projected Ending Balance
—
based on your assumptions and compound growth
Starting Amount
—
initial lump sum
Total Contributions
—
monthly additions only
Investment Growth
—
returns earned over time
Total Invested
—
starting amount plus contributions
Growth Summary
Inputs
Starting amount—
Monthly contribution—
Annual return—
Outputs
Ending balance—
Total invested—
Total growth—
Year-by-Year Breakdown
Year
Start Balance
Contributions
Growth
End Balance
✦ Cal, AI Explanation
Your investment summary appears here after calculation.
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Growth Notes
Time is often the biggest driver of compound growth. Longer periods can change outcomes materially.
Monthly contributions can have a large long-run effect even when the starting balance is modest.
Higher return assumptions increase projected value, but also increase forecasting uncertainty.
This is an estimate, not a guarantee. Actual market returns can vary widely year to year.
This calculator estimates how an investment may grow over time using a starting balance, an assumed annual return, a chosen compounding frequency, and optional monthly contributions. It is designed to show how compound growth can change long-term outcomes.
Why Time Matters
Compound growth becomes more powerful over longer periods because returns are earned on earlier returns. That means the effect of time is often larger than people expect.
Why Contributions Matter
Consistent monthly contributions can materially increase ending balance. Even relatively small recurring additions can produce meaningful differences over long horizons.
Illustrative Growth Examples
Examples below are illustrative only.
Starting Amount
Monthly Contribution
Years
Estimated Return
€10,000
€0
10
Moderate growth
€10,000
€250
10
Higher ending value
€25,000
€500
15
Materially larger growth
€50,000
€1,000
20
Strong compounding effect
Frequently Asked Questions
How does compound growth work?+
Compound growth means returns are earned on both your original capital and on prior growth. Over long periods, that can create a snowball effect.
Are monthly contributions included?+
Yes. You can enter a monthly contribution amount and the calculator will include it in the projection.
Does this guarantee returns?+
No. The output is only an estimate based on the assumptions you enter. Actual market performance is uncertain.
What annual return should I use?+
That depends on the asset class, risk level, fees, tax assumptions, and your forecasting method. Conservative assumptions are generally safer than aggressive ones.
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