Percent Difference Calculator – with Step-by-Step Guide
Calculate the percent difference between two numbers by entering them below, and we’ll also show the steps to solve it.
Percent Difference:
Steps to Solve Percent Difference
On this page:
- Percent Difference Calculator
- How to Calculate Percent Difference
- Percent Difference Formula
- Steps to Find Percent Difference
- Step One: Find the Difference
- Step Two: Find the Average
- Step Three: Divide the Difference by the Average
- Step Four: Convert to a Percentage
- Percent Difference vs. Percent Change
Joe is the creator of Inch Calculator and has over 20 years of experience in engineering and construction. He holds several degrees and certifications.
How to Calculate Percent Difference
Percent difference is a comparison of two numbers of the same measurement. Specifically, it is the difference between two numbers expressed as a percentage.
The percent difference between two values is equal to their difference divided by their average.
So, percent difference can be found by first finding the difference between the numbers, then finding the average of the numbers, and then dividing. Finally, multiply by 100 to get a percentage.
Percent Difference Formula
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.
Steps to Find Percent Difference
The difference can be solved in three easy steps.
Step One: Find the Difference
The first step in solving the 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 the 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.
Step Four: Convert to a Percentage
To express the difference as a percentage, simply 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%
Percent Difference vs. Percent Change
It’s important to note that percent difference is not the same thing as percent change.
As stated above, the difference is the difference between two numbers expressed as a percentage. Percent change is the change from one value to another value.
If you’re actually trying to solve the amount of change from one value to another, 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.
