%
Free Online Calculator
Simple Interest Calculator
Calculate simple interest and total amount quickly using principal, annual interest rate, and time.
Investment Details
Enter the values below to calculate your simple interest.
$
%
💡
Formula: Simple Interest = Principal × Rate × Time. The rate is treated as an annual percentage.
💰
Calculation Result
Your simple interest breakdown
Simple Interest
$1,500.00
Interest earned over 3 years
$10,000.00
Principal
5%
Annual Rate
3 Years
Time Period
$11,500.00
Total Amount
Calculation
$10,000 × 5% × 3 = $1,500.00
Principal
The original amount of money invested or borrowed before interest.
Interest Rate
Enter the annual interest rate as a percentage, such as 5 for 5%.
Time Period
Choose years, months, or days. Months and days are converted to a fraction of a year.
Simple Interest Reference
Quick reminders for the calculation.
I = PRT
Interest formula
A = P + I
Total amount
5% = 0.05
Rate as decimal
12 months
= 1 year
Result copied