Compound Interest Calculator
Calculate future wealth value using compound interest formulas. Fast, free, and fully client-side.
Calculator Inputs
How the Compound Interest Calculator Works
Compound interest calculates exponential wealth accumulation by reinvesting earned interest back into the principal balance. Unlike simple interest, compound interest earns returns on both original capital and previously accumulated interest.
Formula
A = P × (1 + r/n)^(n × t)
Where A is future value, P is initial principal, r is annual interest rate (decimal), n is compounding frequency per year, and t is term in years.
Calculation Example
Investing $10,000 at a 7% annual interest rate compounded monthly for 10 years yields a future balance of $20,096.61 ($10,096.61 in compound interest).
Frequently Asked Questions
What is the Rule of 72?
Divide 72 by your annual interest rate to estimate the number of years required for an investment to double in value.
How does compounding frequency impact returns?
More frequent compounding (e.g. monthly vs annual) yields higher returns because interest is credited and reinvested sooner.