Compound Interest Calculator

Growth of a lump sum with yearly → daily compounding frequencies.

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About this calculator

Compound interest earns interest on interest. Over long horizons this snowball effect dominates — the difference between 6% and 10% over 25 years is not linear but exponential.

Einstein allegedly called compounding the eighth wonder of the world; whether he said it or not, the mathematics holds.

Formula

A = P × (1 + r/n)^(n×t)

Frequently Asked Questions

What is the Rule of 72?

Divide 72 by the annual return rate to estimate doubling time. At 8% money doubles roughly every 9 years.

Why choose different compounding frequencies?

Banks quote rates with specific compounding conventions (FDs usually quarterly). Match the frequency to get accurate results.