APR Calculator
The APR Calculator converts a periodic interest rate into an annual percentage rate by multiplying it by the number of periods in a year. The formula used is: APR = Periodic Rate × Periods per Year.
Formula
APR = Periodic Rate × Periods per Year
- The APR Calculator updates instantly as you change the periodic rate or number of periods.
- Formula: APR = Periodic Rate × Periods per Year
- Input definitions: • Periodic Rate %: the interest rate charged in one period (e.g. monthly) • Periods per Year: how many periods make up a year (12 for monthly)
- This is the nominal APR, which does not compound between periods.
- For monthly rates use 12 periods, for weekly use 52, and for daily use 365.
- APR lets you compare loans on a common annual basis, but it excludes one-off fees.
Example Calculation
Inputs
- Periodic Rate %: 1
- Periods per Year: 12
A 1% monthly rate over 12 months gives APR = 1 × 12 = 12%.
Frequently asked questions
What is APR?
The annual percentage rate expresses the cost of borrowing on a yearly basis. Here it is the periodic rate multiplied by the number of periods per year.
How is APR different from APY?
APR is the simple annualized rate with no compounding, while APY (yield) includes the effect of compounding and is therefore higher.
What should I enter for periods?
Use the number of compounding or billing periods per year — 12 for monthly, 52 for weekly, 365 for daily.
Does APR include fees?
This calculation uses only the interest rate. A lender's stated APR may also fold in certain fees, which can make it higher.
How do I read the result?
A higher APR means more interest cost per year. Use it to compare loans or credit products on equal footing.