Simple Interest Calculator
Free online Simple Interest Calculator.
Calculator
How to Use
- Enter the required values
- Click Calculate to see the result
- Review the detailed output
Formula
I = P x r x t, where I = interest, P = principal, r = annual rate (decimal), t = time in years. Total = P(1 + rt). Interest earned only on original principal.
Example Calculations
Loan Interest
Input: Principal: $5,000, Rate: 6%, Time: 3 years
Result: Interest: $900, Total: $5,900
Savings
Input: Principal: $10,000, Rate: 4%, Time: 5 years
Result: Interest: $2,000, Total: $12,000
Find Rate
Input: Principal: $8,000, Interest: $1,200, Time: 3 years
Result: Rate: 5% per year
About This Calculator
Free online simple interest calculator. Calculate instantly in your browser with our easy-to-use tool. No sign-up required.
Our simple interest calculator is free, easy to use, and provides instant results. All calculations are performed in your browser for privacy and speed.
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Frequently Asked Questions
What is simple interest?
Interest on principal only: I = P x r x t. Does not earn on accumulated interest.
Simple vs compound interest?
Simple on principal only. Compound on principal + accumulated. Compound grows faster over time.
When is simple interest used?
Personal loans, auto loans, short-term borrowing, bonds, some savings accounts.
Total with simple interest?
A = P(1 + rt). $1,000 at 5% for 3 years = $1,150.
Simple interest for savers?
Less beneficial than compound. For long-term savings, seek compound interest accounts.