What is compound interest?

Compound interest is interest calculated on both the initial principal and the accumulated interest from prior periods, causing your balance to grow exponentially over time.

Compound Interest Calculator

Calculate future value from starting balance, return, years, and compounding frequency.

This tool runs in your browser. None of your data is saved or sold.

Starting amount ($)

Annual return (%)

Years (years)

Compounds per year (years)

Contribution each period

Inflation rate (%)

About This Calculator

Compound interest is what makes long-term investing so powerful — you earn returns not just on your original investment, but on the interest/gains accumulated over time. This calculator shows your future value, total growth, and total contributions so you can see exactly how much of your ending balance came from the market versus your own savings.

Estimates only — not financial, tax, legal, or investment advice. Verify important results with a qualified professional before making decisions.

FV = PV×(1+r/n)^(n×t) + C×((1+r/n)^(n×t)−1)/(r/n); total contributions = PV + C×n×t; inflation-adjusted FV = FV ÷ (1+i)^t