How to Calculate Percentage Decrease?

Whether you are calculating a store discount, tracking weight loss, or analyzing a drop in website traffic, calculating the percentage decrease is a very useful math skill. Here is the standard formula:

Step-by-Step Example

Imagine you are buying a jacket. The original price was $120, but it is on sale for $90. What is the percentage decrease (discount)?

1. Subtract the new value from the original value: 120 - 90 = 30 (This is the absolute price drop).
2. Divide that number by the absolute original value: 30 / 120 = 0.25.
3. Multiply by 100 to convert to a percentage: 0.25 × 100 = 25%.

The price dropped by exactly 25%. You can use our free calculator above to find the exact percentage difference between any two numbers instantly!