Math & StatisticsFormula-based · Runs in your browser

Percent Error Calculator

Compare an observed value with an exact or accepted value.

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Inputs

Enter the values you know. Optional fields may be left empty.

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Result

Updates as valid inputs change.

Calculated locally
Percent error
Absolute error
Signed error

Saved locally, explained clearly

Drafts, calculations, scenarios, and workflow progress stay in this browser unless you export them.

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Calculation steps

Follow what happened from the selected formula to the displayed answer.

Show substituted values and intermediate working
Calculate current inputs to see the working.
  1. 1

    Formula selected

    The calculator uses the following formula or method.

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

  2. 2

    Values entered

    Your values are placed into the calculation.

    Enter values to see what is used in this step.

  3. 3

    Result calculated

    The formula or method produces the following result values.

    Results will appear after a successful calculation.

  4. 4

    Answer formatted

    Displayed values are rounded and formatted using each output’s configured precision.

Scenario comparison

Save working scenarios, then select two or three to compare. Formula versions and inputs remain visible.

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Recent calculations

Successful calculations are retained locally according to your privacy settings.

No local history for this calculator yet.

Data and privacy

How it works

Absolute error is divided by the magnitude of the accepted value. The signed error shows whether the observation is above or below it.

Input query strings and outputs

Use an input name in this page’s URL as ?name=value, and join additional inputs with &. Portable shared links may instead use the compact ?ac= state parameter.

Input query strings

2
  • ?observed= Observed value

    Number · Required · Default: 9.7

  • ?exact= Exact value

    Number · Required · Default: 10

Outputs

3
  • percentError Percent error

    Percentage · Primary output

  • absoluteError Absolute error

    Number

  • signedError Signed error

    Number

Sources
  • No external reference is listed for this calculator. Its formula and variable definitions are shown above.
Limitations
  • Results depend on the selected method and input assumptions. Displayed decimals may be rounded; retain appropriate precision for later calculations.