Free · Instant · Private
Percentage Decrease Calculator
Enter the original value and the new value to work out the percentage decrease, with the absolute change and each step shown.
How this percentage decrease calculator works
The calculator divides the fall by the original value, not by the new value, because a decrease is measured from where you started. A price falling from 200 to 150 therefore decreases by 25%, and a value halving decreases by 50%. A value can never decrease by more than 100% if it stays at or above zero, because a 100% decrease already takes it to zero. If the original value is zero, the result is undefined, so the calculator explains that instead of showing a number. For the opposite direction, use the percentage increase calculator, and for all five percentage calculations, use the percentage calculator.
Note: For general information only. Results are rounded to two decimal places.
Frequently asked questions
How is percentage decrease calculated?
Subtract the new value from the original value, divide by the original value, and multiply by 100. For example, (200 − 150) ÷ 200 × 100 = 25%.
Why is a decrease from 100 to 80 not the same as an increase from 80 to 100?
Because the base changes. The decrease divides by 100, giving 20%, while the increase divides by 80, giving 25%. For a direction-free comparison, use the percentage difference calculator on the main page.
What if the new value is higher than the original?
The percentage decrease is then negative, which means the value actually rose. Use the percentage increase calculator if you want the rise expressed as a positive percentage.