Percentage Change Calculator (Advanced) Formula
Understand the math behind the percentage change calculator (advanced). Each variable explained with a worked example.
Formulas Used
Pct Change
pct_change = original != 0 ? ((new_val - original) / abs(original)) * 100 : 0Pct Diff
pct_diff = (original + new_val) != 0 ? abs(new_val - original) / ((abs(original) + abs(new_val)) / 2) * 100 : 0Abs Change
abs_change = new_val - originalRatio
ratio = original != 0 ? new_val / original : 0Variables
| Variable | Description | Default |
|---|---|---|
original | Original Value | 80 |
new_val | New Value | 92 |
How It Works
Percentage Change vs Percentage Difference
Percentage Change
% Change = ((New - Original) / Used when there is a clear "before" and "after" value. % Difference =Original ) × 100 Percentage Difference
New - Original / (( Old + New
Used when comparing two values without a clear reference (e.g., comparing two measurements).
Worked Example
A value changed from 80 to 92.
- 01% Change = (92 - 80)/80 × 100 = 12/80 × 100 = 15%
- 02% Difference = 12/86 × 100 ≈ 13.95%
- 03Absolute change = 12
- 04Ratio = 92/80 = 1.15
Frequently Asked Questions
What is the difference between percentage change and percentage difference?
Percentage change uses the original value as the denominator (directional). Percentage difference uses the average of both values (symmetric, no direction).
Can percentage change be negative?
Yes, a negative percentage change indicates a decrease. For example, going from 100 to 80 is a -20% change.
What is percentage error?
Percentage error = |experimental - theoretical| / |theoretical| × 100. It measures the accuracy of a measurement against a known standard.
Learn More
Guide
How to Calculate Percentages - Complete Guide
Learn how to calculate percentages step by step. Covers finding a percentage of a number, percentage change, reverse percentages, and real-world applications.
Ready to run the numbers?
Open Percentage Change Calculator (Advanced)