Compound Interest Calculator

Calculate investment growth with compound interest. See how your money grows over time.

Investment Details
$
%
years

$
Results
Future Value
$19,671.51
Total Interest Earned
$9,671.51
Total Contributions
$10,000.00
Interest Rate Effect
96.72%
Money Doubled In
~10.2 years
Growth Over Time
Year-by-Year Breakdown
Year Starting Balance Contributions Interest Ending Balance
Understanding Compound Interest

The Power of Compounding: Albert Einstein reportedly called compound interest the "eighth wonder of the world." Your money earns interest, then that interest earns interest, creating exponential growth.

The Rule of 72: To estimate how long it takes to double your money, divide 72 by your interest rate. At 7% interest, your money doubles in about 10.3 years (72 ÷ 7 = 10.3).

How to Use Compound Interest Calculator

  1. Enter your initial investment (principal)
  2. Set the annual interest rate
  3. Choose the time period in years
  4. Select compounding frequency
  5. Optionally add regular monthly contributions
  6. View the growth chart and final balance

About Compound Interest Calculator

See exactly how your investments will grow with compound interest. Enter your principal amount, interest rate, and time period to see future value. Compare different compounding frequencies (daily, monthly, yearly). Visualize growth with an interactive chart. Perfect for retirement planning and investment decisions.

Frequently Asked Questions

What is compound interest?

Compound interest is interest calculated on both the initial principal and the accumulated interest. It's "interest on interest" that makes your money grow exponentially.

How does compounding frequency affect growth?

More frequent compounding (daily vs yearly) results in slightly higher returns because interest is added and starts earning more interest sooner.

What's a realistic interest rate to use?

Stock market average is about 7-10% long-term. Savings accounts are 0.5-5%. Bonds are typically 3-6%. Use conservative estimates for planning.

Is this calculator accurate?

Yes, we use the standard compound interest formula. Results are mathematically accurate for the inputs provided.