What is percentage difference?

Percentage difference compares two values by finding the absolute difference between them and dividing it by their average, then multiplying by 100.

What is the difference between percentage difference and percentage change?

Percentage difference compares two values without treating either one as the starting value. Percentage change uses a starting value as the reference and calculates how much the value has increased or decreased.

Can I use decimal numbers?

Yes. The calculator accepts whole numbers as well as decimal values.

Can percentage difference be calculated when one value is negative?

Yes. The calculator can compare positive and negative values. The average used in the standard percentage difference formula must not be zero.

Is this percentage difference calculator free?

Yes. The Percentage Difference Calculator is free to use online and performs the calculation directly in your browser.

General & Everyday Calculators

Percentage Difference Calculator

Q: What is the percentage difference formula?

The percentage difference formula is the absolute difference between two values divided by their average, multiplied by 100.

Calculate the percentage difference between two values quickly and accurately using the standard percentage difference formula.

Percentage Difference Calculator

Enter two values below to calculate their percentage difference.

Percentage Difference

First Value —

Second Value —

Absolute Difference —

Average —

What Is a Percentage Difference Calculator?

A percentage difference calculator compares two values and expresses the difference between them as a percentage of their average. Unlike percentage change, percentage difference does not require one value to be treated as the original or starting value.

This makes percentage difference useful when comparing two measurements, experimental results, prices, quantities or other values where neither number is necessarily the baseline. The calculation is performed instantly in your browser.

Why Use Percentage Difference Calculator?

This free online calculator provides a quick way to compare two values without having to perform the percentage difference formula manually.

Instant Calculations

Calculate percentage differences immediately after entering your two values.

Accurate Formula

Uses the standard percentage difference formula based on the absolute difference and average.

Decimal Support

Enter whole numbers or decimal values for more precise comparisons.

Easy to Use

Enter two values, select Calculate and view the percentage difference instantly.

Works Both Ways

Reversing the two values produces the same percentage difference.

Free Online Tool

Use the calculator online without installing software or creating an account.

How to Use Percentage Difference Calculator

Follow these simple steps to calculate the percentage difference between two values.

Enter the first value — Type the first number you want to compare.
Enter the second value — Type the second number in the comparison field.
Calculate the result — Select the Calculate button to perform the calculation.
Review the result — The percentage difference, absolute difference and average are displayed below the calculator.

How to Calculate Percentage Difference

Percentage difference is calculated by finding the absolute difference between two values, dividing that difference by the average of the two values, and multiplying the result by 100. The formula is: |Value 1 − Value 2| ÷ ((Value 1 + Value 2) ÷ 2) × 100.

For example, if two values are 50 and 75, their absolute difference is 25 and their average is 62.5. Dividing 25 by 62.5 and multiplying by 100 gives a percentage difference of 40%.

Percentage Difference Formula

The standard formula uses the absolute difference between the two values, so the result is non-negative. Because both values are treated equally, switching their positions does not change the result.

Percentage Difference vs Percentage Change

Percentage difference and percentage change are related but serve different purposes. Percentage change compares a new value against a specific original value, while percentage difference compares two values without designating either as the starting point. Use percentage change when there is a clear baseline and percentage difference when comparing two independent values.

Percentage Difference Calculation Details

The calculator uses the absolute difference between the two entered values and divides it by their arithmetic mean. The resulting ratio is multiplied by 100 to express the difference as a percentage.

The two values can be whole numbers or decimals, including negative values. The calculation cannot produce a standard percentage difference when the average of the two values is zero, because this would require division by zero. All calculations are performed locally in your browser.

Created by

James William Steven Parker

Creator & Developer of YesTools

James William Steven Parker is a web developer and technology professional with extensive experience in web development, web design, SEO, web hosting, systems analysis and cybersecurity. He created YesTools to provide fast, practical and free online tools for everyday tasks and technical work.

Learn more about James and YesTools

Frequently Asked Questions

Percentage difference compares two values by finding their absolute difference, dividing it by their average and multiplying by 100.

The standard formula is: absolute difference between the two values divided by their average, multiplied by 100.

Percentage difference compares two values without designating a starting value. Percentage change uses an original value as the reference point and measures an increase or decrease from it.

Yes. You can enter both whole numbers and decimal values into the calculator.

Yes. Negative values can be compared, provided that the average of the two values is not zero.

Yes. This percentage difference calculator is free to use online and performs calculations directly in your browser.

Explore More Free Tools

Explore the YesTools collection of free online tools, calculators, converters, generators and utilities.

Browse All Categories