# Periodic Interest Rate Calculator

> Calculate the periodic rate from a nominal annual rate or from an effective annual rate.

Page: https://askcalculators.com/calculator/periodic-interest-rate-calculator/
Definition: https://askcalculators.com/calculator/periodic-interest-rate-calculator/definition.json
JSON Schema: https://askcalculators.com/calculator/periodic-interest-rate-calculator/schema.json
Version: 1.0.0
Maintained by: AskCalculators (software project; not a credentialed reviewer)
Qualified review: pending. Automated checks do not establish professional approval.
Page status: Live
Review status: Pending

## Use
Open the calculator page and enter values. Query-string parameters can restore and bookmark a calculation.
Example: https://askcalculators.com/calculator/periodic-interest-rate-calculator/?annualRateType=nominal&annualRate=6&periodsPerYear=12

## Inputs
- annualRateType: Annual rate type; type=select; required; default=nominal; values=nominal|effective
- annualRate: Annual interest rate; type=percent; required; default=6; min=-99.99; max=1000
- periodsPerYear: Periods per year; type=number; required; default=12; min=1; max=365

## Outputs
- periodicRate: Periodic interest rate; format=percent; primary
- nominalAnnualRate: Equivalent nominal annual rate; format=percent
- effectiveAnnualRate: Equivalent effective annual rate; format=percent

## Formula
nominal: i = j/m; effective: i = (1+EAR)^(1/m) − 1

## Rules
- Empty optional inputs are undefined, not zero.
- Hidden conditional inputs are ignored.
- Do not invent missing required inputs.