# Percent Error Calculator

> Compare an observed value with an exact or accepted value.

Page: https://askcalculators.com/calculator/percent-error-calculator/
Definition: https://askcalculators.com/calculator/percent-error-calculator/definition.json
JSON Schema: https://askcalculators.com/calculator/percent-error-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/percent-error-calculator/?observed=9.7&exact=10

## Inputs
- observed: Observed value; type=number; required; default=9.7
- exact: Exact value; type=number; required; default=10

## Outputs
- percentError: Percent error; format=percent; primary
- absoluteError: Absolute error; format=number
- signedError: Signed error; format=number

## Formula
Percent error = |observed − exact| ÷ |exact| × 100

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