Percent Difference Calculator

What is Percent Difference?

Percent difference measures the relative difference between two values without regard to which is larger. It uses the average of the two values as the reference point.

Formula: Percent Difference = |Value₁ - Value₂| ÷ ((|Value₁| + |Value₂|) ÷ 2) × 100%

Note: This is different from percent change, which uses one specific value as the reference (usually the original/starting value).



This tool compares two numbers and shows the difference in percentage. It uses the average of the two absolute values as the reference.

What Is Percent Difference?

Percent difference measures how far apart two numbers are. It uses the formula:

Percent Difference = |Value₁ - Value₂| ÷ ((|Value₁| + |Value₂|) ÷ 2) × 100%

This calculation differs from percent change. Percent change uses one value as the reference point.

How to Use This Tool

Follow these steps to calculate the percent difference.

  1. Enter the first number in the field labeled "First Value".
  2. Enter the second number in the field labeled "Second Value".
  3. Click the Calculate button.

The tool will display the percent difference with a brief calculation breakdown.

Input Field Details

The "First Value" field accepts any number. The "Second Value" field accepts any number as well. Do not leave fields empty. The tool checks that both values are valid before calculation.

Understanding the Output

The result shows the percent difference between the two numbers. It also displays the absolute difference and average. This helps you see how the result was computed.

Limitations and Special Notes

If both inputs are zero, the calculator shows a zero percent difference. The tool requires valid numbers. If you enter non-numeric values, it will ask you to correct your input.

Examples of Common Use Cases

This tool is useful for students and professionals alike.

Try it now. See the percent difference in real time.