How does compound interest work?

Compound interest means you earn returns on your previous returns. A $10,000 investment at 8% grows to $10,800 after year 1, then earns 8% on $10,800 (not $10,000) in year 2.

What is the Rule of 72?

Divide 72 by the annual return rate to estimate how many years it takes to double your money. At 8% return, your investment doubles approximately every 9 years.

Should I invest a lump sum or regularly?

Regular investing (dollar-cost averaging) reduces timing risk and helps you invest regardless of market conditions. Both approaches outperform holding cash over the long term.

Investment Calculator — Grow Your Investment

The Investment Calculator shows how an initial investment grows over time with compound interest and optional regular contributions. Whether you are investing in stocks, bonds, index funds, or real estate, understanding the long-term growth trajectory helps you make smarter financial decisions. Compound interest — earning returns on returns — is the engine of long-term wealth creation.

Initial Investment($)

Annual Additional Investment($)

Annual Return Rate(%)

Investment Period(years)

Frequently Asked Questions

The S&P 500 has historically returned approximately 10% per year before inflation (about 7% after inflation). Individual results vary significantly based on market conditions.

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