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% Compound Calculator

Investment planning calculator

Compound Interest Calculator

Estimate future value, monthly contribution growth, total principal, and compound earnings directly in your browser.

Future value $0.00
Compound earnings $0.00
Total principal$0.00
Total contributions$0.00
Total return0.00%
Average annualized return0.00%
Principal share0.00%
Earnings share0.00%

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The old basic calculator and the newer helper tools are still available. The homepage is focused on compound interest, while the directory keeps the wider tool collection reachable.

Asset growth trend

Total principalAsset value

Yearly breakdown

YearStarting assetsContributionEarningsEnding assetsCumulative earnings

Reverse calculator

CAGR Calculator

Enter an initial amount, final amount, and investment period to estimate the annualized return.

Annualized return0.00%

What is compound interest?

Compound interest means investment earnings can generate additional earnings in later periods. Unlike simple interest, compounding includes growth on both the original principal and prior accumulated returns. The longer the time horizon, the more visible the compounding effect becomes.

Why use a compound interest calculator?

A compound interest calculator helps estimate long-term investment results before money is committed. It can compare lump-sum investing, monthly contributions, different time horizons, and different assumed annual returns.

Compound interest formula

FV = PV × (1 + r / n) ^ (n × t)

  • FV means future value.
  • PV means initial principal.
  • r means annual return rate.
  • n means compounding periods per year.
  • t means investment years.

FAQ

Are the calculator results exact?

The results are mathematical estimates based on your inputs. Real investment outcomes can be affected by market volatility, fees, taxes, inflation, and product risk.

Is a higher annual return always better?

A higher assumed return creates a higher theoretical result, but it usually also implies higher risk. Return assumptions should be read together with risk tolerance.

Is beginning-of-month contribution better than end-of-month contribution?

With the same assumptions, beginning-of-month contributions are usually slightly higher because money enters the compounding cycle earlier.

Can this be used for fund investing plans?

Yes, it can be used as a rough educational estimate by entering an assumed long-term annual return. It does not predict actual fund performance.

Is this investment advice?

No. This tool is for education and reference only and does not provide investment, tax, legal, or financial advice.