Compound Interest Calculator

Albert Einstein reportedly called compound interest the "eighth wonder of the world." Our Compound Interest Calculator helps you understand why. It shows you how your initial investment can grow exponentially over time as you earn interest on your interest.

Whether you're saving for retirement, a house, or just building wealth, understanding the power of compounding is crucial for financial planning.

How It Works

Compound interest is calculated on the initial principal, which also includes all of the accumulated interest from previous periods on a deposit or loan.

Formula: A = P(1 + r/n)^(nt)

• P: Principal investment amount
• r: Annual interest rate (decimal)
• n: Number of times interest is compounded per year
• t: Number of years

Key Takeaways

• Start Early: Time is the most powerful factor. The longer your money compounds, the faster it grows.
• Frequency Matters: More frequent compounding (e.g., monthly vs. annually) results in slightly higher returns.
• Rate of Return: Even small differences in interest rates can lead to massive differences in final value over long periods.

How to Use

1. Enter your starting "Principal Amount".
2. Input the expected "Annual Interest Rate".
3. Set the "Time Period" in years.
4. Choose how often the interest is compounded (usually Monthly or Annually).
5. The tool will instantly calculate your future balance and total interest earned.