Simple Interest Calculator Online Free
Calculate simple interest, total amount and interest earned instantly. Enter principal, annual rate and time period to estimate loan or savings interest.
Interest Details
Results
Total Amount = Principal + Interest
| Period | Principal | Interest | Total Amount |
|---|
How to Use the Simple Interest Calculator
Calculate interest in three simple steps.
1. Enter principal
Add the original amount borrowed, invested or saved.
2. Add rate and time
Enter the annual interest rate and the time period.
3. View results
See total interest, final amount and period breakdown instantly.
Calculate interest without compounding.
This Simple Interest Calculator is useful for estimating interest on basic loans, savings, short-term lending, educational examples and fixed-rate interest scenarios.
You can calculate interest earned, total amount, average monthly interest, average daily interest and a period breakdown using years, months or days.
What is simple interest?
Simple interest is interest calculated only on the original principal amount. Unlike compound interest, it does not add previously earned interest back into the balance.
The common formula is Interest = Principal × Rate × Time.
When should you use it?
- Estimating basic loan interest
- Calculating short-term savings interest
- Learning the simple interest formula
- Comparing simple interest with compound interest
- Checking fixed-rate interest examples
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Simple Interest Calculator FAQ
Common questions about simple interest calculations.
What is simple interest?
Simple interest is interest calculated only on the original principal amount.
What is the simple interest formula?
The formula is Interest = Principal × Rate × Time. The rate is usually written as a decimal and time is usually measured in years.
Can I calculate interest for months or days?
Yes. This calculator converts months and days into years for the simple interest calculation.
Is this financial advice?
No. This calculator is for educational estimates only and should not be considered financial advice.
What is the difference between simple interest and compound interest?
Simple interest is calculated only on the principal. Compound interest is calculated on both principal and previously earned interest.
Can I change the currency?
Yes. You can choose USD, EUR, GBP or BRL for the output format.
Can I copy the summary?
Yes. Click Copy Summary to copy the main result and calculation details.
Does it work on mobile?
Yes. This simple interest calculator works on desktop, tablet and mobile browsers.