How to calculate percentage increase
Enter the original value and the new value. The formula is: percentage change = ((new - original) / original) x 100. A positive result is an increase; a negative result is a decrease. The absolute change shows the raw difference, and the multiply factor shows how many times larger the new value is.
Percentage change formula
Percentage change = ((New Value - Original Value) / Original Value) x 100. Example: from 80 to 100 = ((100 - 80) / 80) x 100 = 25% increase. From 100 to 80 = ((80 - 100) / 100) x 100 = 20% decrease. Note: a 25% increase followed by a 20% decrease returns to the original value.
FAQ
Is percentage increase the same as percentage difference?
No. Percentage increase or decrease uses the original value as the base and is directional — it tells you how much something changed relative to where it started. Percentage difference uses the average of both values as the base and is symmetric.
Why is a 50% increase and then a 50% decrease not zero?
Because the base changes. If you increase 100 by 50% you get 150. Then decreasing 150 by 50% gives 75, not 100. The multiply factor shown by this calculator makes this easy to see: 1.5 x 0.5 = 0.75.