Percentage Decrease Calculator
Find the percentage decrease from an old value to a new lower value. Enter the original and reduced amounts to get the exact percent drop. Perfect for markdowns, weight loss, and cost savings.
How to use this tool
- Enter old value and new value in the fields above.
- Results update instantly as you type — or click Calculate.
- Read your percentage decrease and the full breakdown beneath it.
Formula
Percentage Decrease = ((Old - New) / |Old|) x 100
How it works
Subtract the new value from the old value, divide by the absolute value of the old value, then multiply by 100.
Worked example
Price drops from 100 to 75
- Difference: 100 - 75 = 25
- Divide: 25 / 100 = 0.25
- Multiply: 0.25 x 100 = 25%
Common mistakes to avoid
- Dividing by the new (lower) value rather than the original old value, overstating the percentage decrease.
- Entering the values in reverse order (new as old, old as new) and getting a percentage increase instead of a decrease.
- Treating the result as the new price rather than the amount reduced; subtract the decrease amount from Old to get the New value.
Key terms
Frequently asked questions
- A jacket costs $120 and is on sale for $90. What is the percentage decrease?
- ((120 - 90) / 120) x 100 = 25%. The price decreased by 25%.
- Can I use this for weight loss calculations?
- Yes. Enter your starting weight as Old and current weight as New. The result is the percentage of your starting weight that you have lost.
- What is the difference between percentage decrease and discount rate?
- They are the same calculation. A 25% discount means the price decreased by 25% relative to the original.