Percentage Difference Calculator
Calculate the percentage difference between two numbers. Perfect for comparing values, measurements, and understanding relative differences.
What is Percentage Difference?
Percentage difference measures the relative difference between two values as a percentage of their average. Unlike percentage change (which compares to an original value), percentage difference compares two values symmetrically.
This calculator is useful for comparing measurements, experimental values, prices, or any two numbers where you want to understand their relative difference without designating one as the "original" value.
How to Use the Percentage Difference Calculator
- Enter value 1: Input the first value you want to compare.
- Enter value 2: Input the second value you want to compare.
- Calculate: Click "Calculate Difference" to see the percentage difference between the two values.
Percentage Difference vs Percentage Change
Percentage Difference
Uses the average of the two values as the base. Formula: |Value1 - Value2| / Average × 100. Both values are treated equally.
Percentage Change
Uses the original value as the base. Formula: (New - Old) / Old × 100. One value is designated as the reference point.
When to Use Each
Use percentage difference when comparing two equal values (like two measurements). Use percentage change when tracking change over time (like before and after).
Common Use Cases
Comparing Measurements
Compare two experimental measurements or readings to see how much they differ.
Price Comparisons
Compare prices from different retailers to see the percentage difference.
Data Analysis
Compare two data points in a dataset to understand their relative difference.
Quality Control
Compare actual measurements to target values to assess quality and accuracy.
Frequently Asked Questions
How is percentage difference calculated?
Percentage difference = |Value1 - Value2| / ((Value1 + Value2) / 2) × 100. The absolute difference is divided by the average of the two values.
Why use the average instead of one value?
Using the average treats both values equally, making it symmetric. This is useful when neither value is clearly the "original" or reference point.
Can percentage difference be over 100%?
Yes, if one value is much larger than the other, the percentage difference can exceed 100%. For example, comparing 10 and 100 gives a 163.64% difference.
What if the values are the same?
If both values are identical, the percentage difference is 0%, indicating no difference between the values.
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