Finance
Compound Interest Calculator
Enter a principal, annual rate, term and compounding frequency — plus optional monthly contributions — to project your final balance, total contributions and total interest earned, with the formula shown.
Examples
Input
$1,000 · 5% · 10 yr · monthly
Output
≈ $1,647 balance · $647 interest
How to use Compound Interest Calculator
Enter your starting amount
Type the principal, annual rate and number of years.
Choose compounding
Select how often interest compounds, from annually to daily.
Add contributions
Optionally add a monthly contribution to see accelerated growth.
Why use this tool
Final balance projection
Separates contributions from interest
Flexible compounding frequency
Optional monthly deposits
Frequently asked questions
A = P(1 + r/n)^(nt) for the principal, plus the future value of regular monthly contributions compounded at the matching rate.
Each monthly deposit earns interest from the month it's added until the end of the term, using a monthly rate derived from your compounding frequency.
Discussion
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