Compound Interest Calculator

Calculate the power of compound interest and see how your investments grow exponentially over time. Compare different compounding frequencies and contribution strategies.

Investment Details

Regular Contributions

Optional: Add regular contributions to see their compound growth

Compound Interest Results

Final Amount: $0
Total Interest Earned: $0
Total Contributions: $0
Annualized Return: 0.00%

Growth Breakdown

Principal Growth: $0
Contributions Growth: $0
Power of Compounding: $0

Comparison Insights

Simple Interest: $0

Compounding Advantage: $0

Growth Multiple: 0.00x

Tip: More frequent compounding = higher returns

Growth Visualization

This chart shows how your investment grows over time with compound interest

Understanding Compound Interest

Compound interest is the interest earned on both the initial principal and the accumulated interest from previous periods. Often called "interest on interest," compound interest is the foundation of wealth building through investing.

Compound Interest Formula

The compound interest formula is:

A = P × (1 + r/n)^(n×t)

Where: A = final amount, P = principal, r = annual rate, n = compounding frequency, t = time in years

Why Compound Interest Matters

  • Exponential Growth: Interest earns interest, creating a snowball effect
  • Time is Money: Starting early maximizes the power of compounding
  • Regular Contributions: Consistent additions accelerate growth
  • Frequency Matters: More frequent compounding increases returns
  • Long-term Wealth: Foundation of retirement planning and wealth building

Compounding Frequencies

Frequency Compounding Periods Common Use Impact
Annually 1 per year Some CDs, bonds Lowest returns
Quarterly 4 per year Some investments Moderate increase
Monthly 12 per year Savings accounts, loans Significant boost
Daily 365 per year High-yield savings Maximum returns

The Rule of 72

The Rule of 72 is a quick way to estimate how long it takes for an investment to double at a given interest rate. Simply divide 72 by the annual interest rate.

Years to Double = 72 ÷ Annual Rate

Example: 8% rate ? 72 ÷ 8 = 9 years to double your money

Regular Contributions

Regular contributions, also known as dollar-cost averaging, reduce the impact of market volatility and ensure consistent investing. Each contribution earns compound interest from the moment it's invested.

Real-World Applications

  • Retirement Accounts: 401(k)s and IRAs grow through compounding
  • Savings Accounts: High-yield savings compound daily
  • Investment Portfolios: Stocks and funds compound annually
  • Debt Management: Credit card interest compounds against you
  • Business Growth: Reinvested profits compound for business owners

Tip: Compound interest is often called the "eighth wonder of the world" because of its incredible power to build wealth. Start investing early, contribute regularly, and let compounding work its magic over time. Even small amounts invested consistently can grow into substantial sums.

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