Percentage Change Calculator
Enter the original and new value to calculate percentage increase or decrease.
Percentage Change — Formula & Guide
Formula
% Change = ((New Value − Old Value) / |Old Value|) × 100
Positive = increase • Negative = decrease.
Example: price $80 → $100
((100 − 80) / 80) × 100 = +25%
Example: temperature 40°C → 32°C
((32 − 40) / 40) × 100 = −20%
Percentage Change vs Percentage Difference
% Change is directional — one value is the reference (old value).
% Difference is symmetric — no reference; just the gap between two values.
