Compound Interest Calculator

See how an initial investment and monthly contributions grow over time. Use the suggested returns (e.g. high-yield savings, bonds, equities) or enter your own. Toggle comparison to compare two scenarios side by side. All amounts in USD.

Your scenario

Initial investment ($)Monthly contribution ($)Expected annual return (%)

Years

Compare with another scenario

Growth over time

Results

Your result

$300,850.72

Total contributed: $130,000.00 · Growth: $170,850.72

How compound interest works

Compound interest means you earn returns on your initial investment and on past gains. Over time, the growth portion of your balance (the gap between what you put in and your total balance) gets larger—that’s the power of compounding. The chart shows your cumulative contributions and your total balance so you can see that gap grow.

More tools

Back to all tools · The Money Maniac