Percentage Difference Calculator
Compare two numbers and get the percentage difference.
CalculatorsLast updated August 2026
Percentage difference22.22%
Unlike percentage increase, this treats 80 and 100 as equals — neither is the “original” value.
Value A · 80
Value B · 100
How to use it
- 1Enter Value A and Value B — the order doesn't matter.
- 2The tool calculates their difference relative to their average automatically.
- 3Read the percentage difference, compare the two values on the bar chart below, and copy the result.
Example
80 and 100 have a 22.2% difference: |80 − 100| ÷ ((80 + 100) ÷ 2) × 100 = 22.2.
How it works
Percentage difference compares two values as equals, using their average as the base rather than treating one as the “before” value: |A − B| ÷ ((A + B) ÷ 2) × 100. Use this when neither number is clearly the original — for a before/after comparison, use the Percentage Increase Calculator instead. If the two values are opposite in sign and happen to average to zero, the calculator explains why no result can be shown rather than dividing by zero.
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