Comprehensive Calculator Guide
The percentage difference between two values is their gap divided by their average, times 100. A product at SAR 120 in one shop and SAR 100 in another differs by 20 ÷ 110 × 100 = 18.18%. Use it when neither value is the baseline, so the order does not change the answer.
Why divide by the average?
Taking the second shop as the base says the first is 20% dearer; taking the first says the second is 16.67% cheaper. Dividing by the average gives one fair figure, 18.18%, whichever way round.
Use percentage change when there is a clear before and after, such as an old and a new salary. Use percentage difference for two equal-standing values: two shops, two instruments, two students.
How to Use
- 01Enter the first value.
- 02Enter the second value; order does not matter.
- 03Read the percentage difference and the absolute gap.
Formula Used
Percentage difference = |a − b| ÷ ((a + b) ÷ 2) × 100Practical Examples
Example 1: two shops
SAR 120 and SAR 100: a gap of 20 over an average of 110, 18.18%.
Example 2: two readings
75 and 80: 6.45%.
Example 3: versus percentage change
If 100 was an old price and 120 the new one, the change is 20%, measured from the old price.
Important Tips
- State which method you used, since the two give different numbers.
Common Mistakes to Avoid
- Using percentage difference for before-and-after comparisons.
- Dividing by one of the values instead of their average.
Frequently Asked Questions
- How do I calculate percentage difference?
- Divide the absolute gap by the average of the two numbers and multiply by 100.
- Does the order matter?
- No, the result is the same either way.
- How is it different from percentage change?
- Change divides by the old value; difference divides by the average.
- Can it exceed 100%?
- Yes, up to 200% when one value is near zero.