Calculate relative percent difference between two values, or rater percent agreement and disagreement counts from agreements and total observations.

Percent Agreement Calculator

Value Comparison
Rater Agreement

Enter the first and second values to calculate the relative percent difference (percent difference).

Related Calculators

Percent Agreement and Percent Difference Formulas

The following example problem outlines the steps and information needed to calculate the relative percent difference (percent difference) between two values, and the formula below also includes rater percent agreement.

\begin{aligned}
PA &= \frac{\text{Agreements}}{\text{Total Observations}} \times 100 \\
RPD &= \frac{\left|V1 - V2\right|}{\left(\frac{V1+V2}{2}\right)} \times 100
\end{aligned}

Variables:

  • PA is the Percent Agreement (%)
  • Agreements is the number of matching ratings/decisions
  • Total Observations is the total number of items rated/observed (agreements + disagreements)
  • RPD is the Relative Percent Difference (percent difference) (%)
  • V1 is the first value 
  • V2 is the second value 

How to Calculate Percent Agreement?

The following steps outline how to calculate percent agreement (rater agreement) or relative percent difference (value comparison), depending on which calculator tab you use.

  1. First, choose the tab you need: Value Comparison (RPD/percent difference) or Rater Agreement (percent agreement). 
  2. For Value Comparison, determine the first value (V1) and the second value (V2). 
  3. Use the correct formula: RPD = |V1−V2| / ((V1+V2)/2) * 100, or PA = (Agreements / Total Observations) * 100.
  4. Finally, calculate the result.
  5. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem : 

Use the following variables as an example problem to test your knowledge (Value Comparison / RPD).

first value = 30

second value = 40

RPD = |V1-V2| / ((V1+V2)/2) *100 = |30-40| / ((30+40)/2) * 100 = 28.57%