Percent Difference Calculator: Formula & Worked Example

Compare two values using their average as the denominator. Calculate instantly in your browser with editable inputs, a worked example and clear assumptions. No account required.

How it is calculated

|A − B| ÷ |(A + B) ÷ 2| × 100

Uses the absolute arithmetic mean as the denominator. A zero mean has no finite percentage difference.

Worked example

Value A

100

Value B

120

Example result: 18.18%

The interactive tool lets you edit every input and reset to this example. Calculations run in your browser.

Questions and answers

Are my calculator inputs sent to a server?

These calculations run in your browser. The calculator does not send your entered values to a calculation server or save them to your learning account.

Why can the result differ from a full spreadsheet model?

Each calculator uses the equation and assumptions shown on this page. Displayed values may be rounded. A workbook with different timing, fees, filters or source data can produce a different result.

Can I use the calculator without an account?

Yes. All 73 calculators are available to guest learners. The worked example shows the default inputs, and Reset restores them.

Related calculators

• Percentage — Find a percentage of a number.
• Average — Calculate the arithmetic mean of values.
• Ratio — Express one quantity relative to another.

All 73 calculators · Practise in the Excel Simulator

Interactive practice runs in your browser.