Percent Difference Calculator – with Step-by-Step Guide

Percent difference is a comparison of two values of the same measurement. Calculate the difference between two values by entering them below and see the steps used to solve.

Percent Difference:

Difference of 75 and 100 is 28.571%

Steps to Solve Percent Difference

Start with the formula to calculate difference percentage
p=|a - b|(a + b) ÷ 2×100
Substitute values in the equation
p=|75 - 100|(75 + 100) ÷ 2×100
Simplify and solve
p=|-25|(175) ÷ 2×100
p=2587.5×100
p=0.28571428571429×100
p=28.571428571429


How to Calculate Percent Difference

The percentage difference of two values can be found by dividing the difference between the values by the average of the values and then multiplying by 100 to get a percentage.

The formula for percent difference is:

p = |a – b| ÷ ((a + b) ÷ 2) × 100

Thus, percent difference p is equal to the absolute value of a minus b, divided by a plus b divided by 2, times 100.

Graph of percentage difference

The difference can be solved in three easy steps.

Step One: Find the Difference

The first step in solving percent difference is to find the difference between the values. This is as simple as subtracting one value from the other.

The key is to use the absolute value of the difference, which just means to drop the negative sign in front of the number if there is one.

Step Two: Find the Average

The second step in calculating percent difference is to find the average of the values. To do this, add the values together to get the sum then divide by 2; this is the average.

Step Three: Divide the Difference by the Average

The next step is to divide the difference of the values by the average. This is the percent difference expressed as a decimal or fraction.

To convert to percentage form multiply by 100.

Example: Find the percent difference of 25 and 48


p = |25 – 48| ÷ ((25 + 48) ÷ 2) × 100
p = |-23| ÷ (73 ÷ 2) × 100
p = 23 ÷ 36.5 × 100
p = 63.014%

The calculator above simplifies finding percentage difference but it uses the formula shown to solve it.

If you’re actually trying to solve the amount of change between 2 values, try our percent change calculator. Of course, our percentage calculator has a ton of tools for calculating percentage that you might also be interested in.