Interest Calculator – Calculate Simple and Compound Interest Online

An interest calculator is a versatile online tool that allows you to calculate both simple interest and compound interest for loans, savings, or investments. Our free online interest calculator provides instant results, helping you understand how your money grows over time or how much interest you owe on a loan.

Whether you are a student, investor, borrower, or finance professional, this interest calculator online simplifies interest calculations and saves time.

What Is an Interest Calculator?

An interest calculator is a digital tool that automatically computes the interest earned or paid on a principal amount. It supports two main types:

Simple Interest (SI)

Calculated only on the principal amount:

SI = P × R × T ÷ 100

Compound Interest (CI)

Calculated on principal and accumulated interest:

CI = P × (1 + R ÷ n)^nt – P

Benefits of Using an Online Interest Calculator

Quick and Accurate

Calculate savings growth or investment returns instantly without manual math.

Compare Options

Evaluate different compounding frequencies to choose the best financial plan.

Free & Accessible

Our compound interest calculator is completely free and works on all devices.

Plan Your Finances

Understand loan interest and repayment amounts for personal or home loans.

How to Use the Interest Calculator

Enter the principal amount.
Enter the annual interest rate (%).
Enter the time period in years.
Choose simple or compound interest calculation.
Click Calculate to view your total amount instantly.

Take control of your financial planning!

Try our interest calculator online today to visualize your investment growth or simplify your loan repayments.