1. What is Percent Difference?

Definition: Percent difference measures the relative difference between two values as a percentage of their average.

Purpose: It's commonly used in scientific experiments, data analysis, and quality control to compare two measured values where neither is considered the "standard" or "correct" value.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( A \) — First measured value
• \( B \) — Second measured value
• \( |A - B| \) — Absolute difference between the values
• \( \frac{(A + B)}{2} \) — Average of the two values

Explanation: The absolute difference between the values is divided by their average, then multiplied by 100 to convert to a percentage.

3. When to Use Percent Difference

Details: Use percent difference when comparing two experimental values, two measurements of the same quantity, or any two numbers where you want to express their difference relative to their average.

4. Using the Calculator

Tips: Enter any two numerical values (positive or negative). The calculator will compute their percent difference. Both values cannot be zero.

5. Frequently Asked Questions (FAQ)

Q1: How is percent difference different from percent change?
A: Percent change compares a new value to an old value (relative to the old value), while percent difference compares two values (relative to their average).

Q2: What does a 0% difference mean?
A: A 0% difference means the two values are identical.

Q3: Can percent difference be more than 100%?
A: Yes, when one value is much larger than the other, the percent difference can exceed 100%.

Q4: What if one value is zero?
A: The calculation works if one value is zero (but not both), though the result will always be 200% in this case.

Q5: When should I not use percent difference?
A: Don't use it when one value is clearly a reference or standard value (use percent error instead), or when comparing more than two values.