What is the difference between percentage change and percentage difference?

Percentage change compares to an original value, while percentage difference compares to the average of two values. Difference is used when neither value is the 'starting point'.

What is the formula for percentage difference?

Percentage Difference = (|Value 1 − Value 2| ÷ ((Value 1 + Value 2) ÷ 2)) × 100. It always gives a positive result.

When should I use percentage difference vs. percentage change?

Use percentage difference when comparing two independent values (e.g., prices of two products). Use percentage change when one value comes before the other (e.g., price this year vs. last year).

Percentage Difference Calculator

Find the percentage difference between two values.

Instant Answer

What is the percentage difference between 40 and 60?

The percentage difference between 40 and 60 is 40%.

The percentage difference between 40 and 60 is 40%. Percentage difference divides the absolute gap by the average of the two values, so neither value is treated as the starting point.

Formula: % Difference = (|V1 − V2| ÷ ((V1 + V2) ÷ 2)) × 100
Definition: Percentage difference is the symmetric relative gap between two independent values, measured against their average rather than against one of them.

Absolute difference:|40 − 60| = 20
Average of both values:(40 + 60) ÷ 2 = 50
Divide and multiply:20 ÷ 50 × 100 = 40%

How to use

1Enter Value 1 — The first number to compare.

2Enter Value 2 — The second number to compare.

3See the difference — The percentage difference is calculated using the average.

Value 1

Value 2

Result

50%

The percentage difference between 30 and 50 is 50%

0%100%

Step-by-step

1Absolute difference:|30 − 50| = 20

2Average of both values:(30 + 50) ÷ 2 = 40

3Divide and multiply:20 ÷ 40 × 100 = 50%

Tab to move between fields · Results update instantly as you typeResults update instantly as you type

Understanding Percentage Difference

Percentage difference measures the relative gap between two values without treating either one as the "starting point." Unlike percentage increase or decrease — which compare a new value to an original — percentage difference uses the average of both values as the reference. This makes it ideal for comparing two independent measurements.

The Formula: (|V1 − V2| ÷ ((V1 + V2) ÷ 2)) × 100

When to Use Percentage Difference

Price comparison: One store sells a blender for $89, another for $119. The percentage difference is 28.85%, helping you see how far apart the prices are regardless of which you consider "base."
Scientific measurements: Two lab instruments measure a sample as 4.82g and 5.01g. The 3.87% difference indicates good agreement between instruments.
Performance metrics: Team A completed 145 tasks while Team B completed 168. The 14.70% difference quantifies the productivity gap neutrally.
Survey results: Region A reports 62% satisfaction vs. Region B's 74%. The percentage difference between these rates is 17.65%.

Difference vs. Change

Don't confuse percentage difference with percentage change. If you know which value came first (e.g., last year's revenue vs. this year's), use the Percentage Increase or Percentage Decrease calculator instead. Percentage difference is symmetric — swapping the two values gives the same result.

For a deeper exploration of percentage concepts, check out our complete guide to percentages.

Percentage difference — worked examples

Percentage difference — worked examples
Question	Calculation	Answer	Open
40 vs 60	(\|40 − 60\| ÷ ((40 + 60) ÷ 2)) × 100	40%	Prefilled
30 vs 50	(\|30 − 50\| ÷ ((30 + 50) ÷ 2)) × 100	50%	Prefilled
89 vs 119	(\|89 − 119\| ÷ ((89 + 119) ÷ 2)) × 100	28.85%	Prefilled
145 vs 168	(\|145 − 168\| ÷ ((145 + 168) ÷ 2)) × 100	14.7%	Prefilled
4.82 vs 5.01	(\|4.82 − 5.01\| ÷ ((4.82 + 5.01) ÷ 2)) × 100	3.87%	Prefilled
62 vs 74	(\|62 − 74\| ÷ ((62 + 74) ÷ 2)) × 100	17.65%	Prefilled
100 vs 200	(\|100 − 200\| ÷ ((100 + 200) ÷ 2)) × 100	66.67%	Prefilled

Every figure above is produced by the same calculation engine that powers the calculator on this page.

Calculation method and limitations

Method: The absolute difference is divided by the mean of the two values and multiplied by 100. Swapping the inputs gives the same result.

Limitations

Use percentage change instead when one value is clearly the “before” value.
An average of 0 (for example 5 and −5) has no valid percentage difference.
The result is always positive, so it says nothing about direction.

Method and examples last reviewed August 6, 2026 by the Snap Percent Calc editorial team. All calculations run locally in your browser.

Frequently Asked Questions

Learn more about percentages

Percentage Difference vs Percentage Change: When to Use Each

Percentage difference and percentage change look alike and give different answers. Learn which to use, the exact formulas, and when each is the honest choice.

Read guide

Percent vs Percentage vs Percentage Points: The Full Distinction

"Percent" and "percentage" are often interchangeable, but percentage points are different — and mixing them up can turn a 2-point rise into a 50% headline. Here's the clear rule.

Read guide

How to Calculate Percentage: The Complete Guide

The ultimate guide to percentage calculations. Learn every formula — basic percentage, increase, decrease, difference, reverse, discounts, VAT, tips, and markup. With examples and calculators.

Read guide