Percentage Difference Calculator (With Formula & Steps)

Find the percentage difference between two numbers. Unlike percent change, percentage difference treats both values equally by dividing by their average, so it does not matter which number you enter first. The calculator also shows the percent change from the first value to the second. Example: 50 and 80 differ by 30, which is a 46.15% difference but a 60% increase from 50.

How to use the Percentage Difference Calculator

1. Enter the two numbers you want to compare. The order does not matter.
2. Press Calculate to see the percentage difference.
3. Use the percent change line if one value is a starting value and the other is a new value.

Formula and method

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

Percent change, by contrast, is (New − Old) / |Old| × 100 and depends on which value is the starting point. Example: A = 50, B = 80. |50 − 80| = 30; average = 65; 30 / 65 × 100 = 46.15%.

Frequently asked questions

What is the difference between percentage difference and percent change?

Percent change measures movement from an old value to a new one and uses the old value as the base. Percentage difference compares two values with no starting point and uses their average as the base.

When should I use percentage difference?

Use it when two values are peers, such as two measurements, two prices from different stores, or two group averages. Use percent change for before-and-after comparisons.

Can the percentage difference be over 100%?

Yes. For example, 1 and 9 have a difference of 8 and an average of 5, which is 160%.

What happens if one value is negative?

The formula still works but results can be hard to interpret. Percentage difference is mainly meant for positive quantities.

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