Interest Calculator

Calculate simple or compound interest for your investments or loans

Compound Interest: A = P(1 + r)ⁿ

Investment Details

Results

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About this Tool

The Interest Calculator computes both simple and compound interest, helping you understand how investments grow or how much interest you'll owe on a loan. Simple interest is calculated only on the principal amount, while compound interest is calculated on the principal plus accumulated interest, leading to exponential growth over time.

Common Use Cases

Investment Projections

Project the future value of your savings or investments using either simple or compound interest.

Loan Cost Analysis

Understand the total interest you'll pay on a loan over its term.

Comparing Savings Accounts

Compare how different interest types and rates affect your savings growth.

Educational Tool

Learn the fundamental difference between simple and compound interest and see the power of compounding in action.

Pro Tips

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    The Power of Compounding

    Compound interest generates significantly more returns over long periods compared to simple interest because you earn interest on your interest.

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    Start Early

    The earlier you start investing, the more time your money has to grow with compounding, even with small amounts.

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    Impact of Rate and Time

    Higher interest rates and longer time periods dramatically increase the amount of interest earned, especially with compounding.

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    Interest on Debt

    Remember that compound interest also works on debt like credit cards, which is why balances can grow quickly if not paid off.

Frequently Asked Questions