Calculate simple and compound interest for savings or loans. Free interest calculator with detailed breakdowns.
An interest calculator helps you understand how your money grows over time through the power of interest. Whether you're saving money in a bank account, investing in bonds, or borrowing money, interest plays a crucial role in determining the final amount. This calculator handles both simple interest and compound interest calculations.
Simple interest is calculated only on the original principal amount, while compound interest is calculated on both the principal and accumulated interest. Compound interest is what makes savings accounts and investments grow exponentially over time. Albert Einstein reportedly called it the eighth wonder of the world, and understanding it is key to building wealth.
If you invest $10,000 at 5% annual interest compounded annually for 10 years: A = 10,000 × (1 + 0.05/1)^(1×10) = 10,000 × 1.62889 = $16,289. Your total interest earned is $6,289. With simple interest, you would earn only $5,000 (10,000 × 0.05 × 10), showing the power of compounding.