1. What is Percentage Difference?

Percentage difference measures how much two values differ relative to the original value (Value A). It's commonly used to compare an old value with a new value, or to measure change between two quantities.

2. How Does the Calculator Work?

The calculator uses the percentage difference formula:

Where:

• \( A \) — Original value (Value A)
• \( B \) — New value (Value B)
• \( |A - B| \) — Absolute difference between values

Explanation: The formula calculates what percentage of the original value (A) the absolute difference between the two values represents.

3. When to Use Percentage Difference

Details: Percentage difference is useful when comparing:

• Before and after measurements
• Experimental results vs control values
• Price changes over time
• Performance improvements

4. Using the Calculator

Tips:

• Enter both values (must be positive numbers)
• Value A is typically the original or reference value
• Result shows how much Value B differs from Value A as a percentage

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between percentage difference and percentage change?
A: Percentage difference is symmetric (uses absolute value) while percentage change is directional (can be positive or negative).

Q2: Can percentage difference be more than 100%?
A: Yes, if Value B is more than double Value A, the percentage difference will exceed 100%.

Q3: What if Value A is zero?
A: The calculation is undefined when Value A is zero (division by zero). The calculator requires Value A > 0.

Q4: How is this different from percentage error?
A: Percentage error compares a measured value to a known or accepted value, while percentage difference compares any two values.

Q5: When would I use relative percent difference instead?
A: Relative percent difference (RPD) divides by the average of the two values and is used when comparing two experimental measurements.