Compare values

Percentage Difference Calculator

Compare two values without treating either one as the original baseline. The order of the values does not change the result.

Live calculation
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How this calculator works

Percentage difference = |A − B| ÷ ((|A| + |B|) ÷ 2) × 100

Percentage difference is best when two measurements are peers. If one value is explicitly old and the other is new, percentage change is usually the better calculation.

Example: 80 and 100

The absolute difference is 20 and the average is 90, so the percentage difference is 22.22%.

Frequently asked questions

Does order matter for percentage difference?

No. Swapping the two values produces the same percentage difference.

When should I use percentage change instead?

Use percentage change when one value is the starting or original value and the other is the ending value.