Percentage Difference Calculator
Compare two numbers that are on equal footing — two quotes, two measurements, two products' prices — and get the difference as a percentage of their average.
Runs in your browser
How to use
- Enter value A.
- Enter value B.
- Read the percentage difference, absolute difference and average.
How it works
Percentage difference = |A − B| ÷ ((A + B) ÷ 2) × 100. Using the average as the base makes the result symmetric: comparing 40 with 50 gives the same answer as comparing 50 with 40 (22.22%).
Use percentage change instead when one value clearly comes first (an old and a new price).
Examples
- Two quotes
- 1,200 vs 1,350 → 11.76% difference.
- Lab measurements
- 9.8 vs 10.1 → 3.02% difference.
Common uses
- Comparing supplier quotes
- Checking agreement between measurements
- Comparing prices between shops
Privacy & security
This tool runs entirely in your browser. Your files and text are never uploaded to our servers — processing happens on your device and results are created locally. How each tool handles files
Frequently asked questions
Percentage difference vs percentage change?
Change uses the first value as the base and has a direction (+/−). Difference uses the average and is always positive.
Can the result exceed 100%?
Yes, up to 200% when one value is zero.
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