Calculate the percent difference between two values A and B. Use this when you need the relative difference without a defined direction.
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% Difference = |A − B| / ((A + B) / 2) × 100What it is, who it's for, how it works and why you'd use it.
A Percent Difference Calculator computes the relative difference between two values as a percentage of their average. It has no directional bias — neither value is 'before' or 'after'.
It is for researchers, analysts, and business users who need to compare two measurements, test results, or data points without implying which came first.
The formula |A − B| / ((A + B) / 2) × 100 uses the average of the two values as the reference point, making the result symmetric.
Unlike percentage change, it does not require you to designate a 'before' and 'after' — ideal for comparing two independent measurements.