What is percentage difference?
Percentage difference describes how far apart two values are relative to their average. The order of the values does not affect the result.
Percentage difference example
For 80 and 100, the absolute difference is 20 and the average magnitude is 90. Dividing 20 by 90 and multiplying by 100 gives approximately 22.22%.
Percentage difference vs percentage change
Percentage difference treats both values equally. Percentage change uses the original value as its baseline and shows an increase or decrease, so it can produce a different result.
When to use percentage difference
It is useful for comparing two measurements, estimates, experimental results or values from separate groups when neither is the established reference.
Zero and negative values
The calculator uses magnitudes in the average denominator so comparisons involving negative values remain non-negative. If both values are zero, their percentage difference is reported as 0%.