Compound Interest Calculator
See how your money grows over time with compound interest vs. simple interest.
You invested
$10,000
Interest earned
$36,610
Final balance
$46,610
Growth Over Time
Understanding Compound Interest
Compound interest is interest earned on both your original investment and previously earned interest. Albert Einstein reportedly called it the "eighth wonder of the world" — and for good reason. It's the engine behind long-term wealth building.
The formula is A = P(1 + r/n)^(nt), where P is principal, r is the annual rate, n is compounding frequency, and t is years. Our calculator visualizes this growth with an interactive chart comparing compound vs. simple interest.
The Power of Time
Starting early matters more than investing more. $10,000 invested at 8% for 30 years grows to $100,627 — a 10x return. The same amount for just 20 years grows to only $46,610. Those extra 10 years more than doubled the final amount, thanks to compound interest.