Simple Interest Calculator
⚡ Calculate simple interest instantly. Find SI, principal, rate, or time with step-by-step solutions. 100% free.
The Best Simple Interest Calculator for Students
Our simple interest calculator is perfect for math homework and classroom learning. Unlike other calculators, we show you EXACTLY how we calculated the answer with detailed step-by-step solutions. Perfect for understanding interest on savings and school projects. No signup, no ads, just instant accurate results.
Simple Interest
SI = (P × R × T) / 100P = Principal, R = Rate (%), T = Time (years)
Total Amount
A = P + SI = P(1 + RT/100)Total amount after interest
Examples
$1000 at 5% for 3 years
$5000 at 8% for 2 years
Frequently Asked Questions
Is this simple interest calculator free?
Yes! 100% free with no signup required and no ads. We believe financial tools should be accessible to everyone.
What is the difference between simple and compound interest?
Simple interest is calculated only on the principal, while compound interest is calculated on principal plus accumulated interest.
When is simple interest used?
Simple interest is often used in school math problems, bank savings accounts, and basic financial calculations.