Interest Calculator

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Calculate simple or compound interest on a starting amount over any number of years.

How the calculation works

Choose simple interest, where interest is only earned on the original amount, or compound interest, where earned interest is added to the balance. A yearly table shows how the balance grows.

Formula used

Simple: A = P × (1 + r × t); Compound: A = P × (1 + r/n)^(n×t)

Example

$10,000 at 5% compounded monthly for 10 years grows to $16,470.09, an effective annual rate of 5.116%.

Frequently asked questions

Which is better, simple or compound?

For a saver, compound interest earns more because interest earns interest.

What is the effective annual rate?

The real yearly growth rate after compounding is taken into account.

Results are estimates for general information only and are not professional financial, medical or legal advice.