Percentage Difference Calculator (With Formula)

What is Percentage Difference?

Percentage difference is used when you want to compare two values that are of the same kind. It shows how much one value differs from another relative to their average. Unlike percentage change, percentage difference does not have a specific "starting" or "ending" value.

Percentage Difference Formula

The formula to calculate the percentage difference between two values (V1 and V2) is:

Percentage Difference = |V1 - V2| / ((V1 + V2) / 2) × 100

Where:

|V1 - V2|: The absolute difference between the two numbers.
(V1 + V2) / 2: The average of the two numbers.

How to Calculate Percentage Difference

Find the absolute difference between the two numbers (subtract them and ignore the negative sign).
Calculate the average of the two numbers (add them and divide by 2).
Divide the difference by the average.
Multiply the result by 100 to get the percentage.

Example: Comparing 20 and 30.

Difference: |20 - 30| = 10
Average: (20 + 30) / 2 = 25
Calculation: (10 / 25) × 100 = 40%

Difference Between Percentage Change and Percentage Difference

It is common to confuse these two, but they serve different purposes:

Percentage Change: Used when there is an old value and a new value (e.g., price increase). It is relative to the *starting* value.
Percentage Difference: Used when comparing two values of the same category without a chronological order. It is relative to the *average* of the two values.

Frequently Asked Questions (FAQs)

Can percentage difference be negative?

No. Since we use the absolute value of the difference, the result is always positive or zero.

When should I use this calculator?

Use it when you want to compare two independent values, like the heights of two buildings or the prices of two different products.

Is this tool free?

Yes, like all Each Convert tools, this calculator is 100% free and does not require any registration or subscription.

Percentage Difference Calculator