Interest Calculator
Calculate simple and compound interest for loans, savings, and investment scenarios. Switch compounding frequency, compare outcomes, and see a visual breakdown of principal versus earned interest.
Enter values and calculate to see interest earned and the final amount.
0%
0
0
0%
0
How to Use the Interest Calculator
- Enter the principal amount, annual interest rate, and the time period.
- Select simple interest or compound interest depending on your scenario.
- If you choose compound mode, pick the compounding frequency such as yearly or monthly.
- Click calculate to see the interest earned, total amount, and comparison view.
What Is Interest?
Interest is the cost of borrowing money or the return earned on money saved or invested. In lending, it is the extra amount paid on top of the principal. In savings and investing, it is the growth earned over time.
Simple vs compound interest
Simple interest is calculated only on the original principal. Compound interest is calculated on the principal plus previously added interest, which can make growth faster over longer periods.
Interest calculation formulas
Simple interest uses the formula SI = P x R x T. Compound interest uses A = P (1 + r/n)^(nt), where n is the number of compounding periods per year. This calculator handles both automatically.
Real-life examples
You can use an interest calculator for savings goals, fixed deposits, investment estimates, or to understand how interest builds on borrowed money. It is also useful when comparing the effect of monthly versus yearly compounding.
Frequently Asked Questions
How do I calculate interest?
Enter principal, rate, and time, then select mode.
Is this tool free?
Yes.
What is compound interest?
Interest calculated on principal plus accumulated interest.
Can I use it for savings?
Yes.