Simple Interest Calculator
Calculate interest earned using the simple interest formula.
Total amount
11,500
How It Works
- 1Enter the principal, annual rate and time period.
- 2View the interest earned and total amount.
Features
- Instant results
- Supports fractional years
Privacy
All calculations happen instantly in your browser. Nothing you enter is ever sent anywhere.
About Simple Interest Calculator
Simple interest is calculated as principal × rate × time (SI = P × R × T / 100 when the rate is a percentage), and the total amount is the principal plus that interest. Unlike compound interest, it grows in a straight line — interest is calculated only on the original principal for the entire period, never on interest already earned.
It's the formula behind some short-term loans, certain fixed-deposit and bond calculations, and it's often the first interest formula taught in finance basics before compound interest is introduced, since it's easier to follow step by step.
Most everyday financial products don't actually use simple interest — savings accounts, credit cards and most long-term investments compound instead, which grows faster over time. Running the same numbers here will understate what a compounding product would actually earn or charge, so it's worth confirming which method a real product uses before comparing.