How does compound interest work?

Compound interest earns interest on both your original deposit and on previously earned interest. The more frequently interest compounds, the faster your money grows.

The S&P 500 has historically returned about 10% annually before inflation. A good ROI depends on the asset class and risk level.

How does inflation affect my investments?

Inflation erodes purchasing power. An investment returning 7% with 3% inflation yields roughly 4% in real terms. Use the Inflation Calculator to see the impact.

Investment Calculators — Free Online Tools (2026)

Grow your wealth with confidence. These investment calculators help you project returns, understand the power of compounding, and plan for long-term financial goals. Compare scenarios to find the strategy that works best for you.

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Compound Interest Calculator — Free Online Financial Tool

Calculate compound interest with monthly contributions using our free calculator. See how your investments grow over time with detailed projections.

ROI Calculator — Free Online Tool

Calculate your return on investment as a percentage to evaluate the profitability of an investment.

Savings Calculator — Free Online Tool

Calculate how your savings grow over time with regular deposits and compound interest.

Inflation Calculator — Purchasing Power Over Time

Calculate how inflation erodes purchasing power over time and find the adjusted value of money across years.

Net Worth Calculator — Calculate Your Total Net Worth

Calculate your net worth by subtracting total liabilities from total assets, with a debt-to-asset ratio.

Future Value Calculator — Free Online Tool

Calculate the future value of a present sum at a given interest rate over multiple periods.

How to Use These Tools Together

1
Calculate your current net worth by listing all assets and liabilities.
2
Determine how much you can set aside monthly for investing.
3
Project how your investments will grow over time with compound interest and regular contributions.
4
Adjust your projections for inflation to understand real purchasing power.
5
Evaluate the return on investment for specific opportunities.

Key Terms Glossary

Compound Interest: Interest calculated on both the initial principal and the accumulated interest from previous periods.
ROI: Return on Investment, a percentage measuring the gain or loss relative to the amount invested.
Inflation: The rate at which the general price level of goods and services rises, reducing purchasing power over time.
Net Worth: The total value of all assets minus all liabilities, representing your overall financial position.
Future Value: The projected worth of an investment at a specific date in the future based on an assumed growth rate.
Diversification: Spreading investments across different asset classes to reduce risk.

Frequently Asked Questions

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