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Percentage Decrease Calculator

Use this free online percentage decrease calculator to find how much a value has dropped. Enter the original and new values to calculate the percentage reduction instantly.

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Formula

Percentage Decrease = ((Old - New) / Old) × 100

Subtract the new value from the old value, divide by the old value, and multiply by 100.

Worked Example

Old value: 100, New value: 75 Step 1: Difference → 100 - 75 = 25 Step 2: Divide by old → 25 / 100 = 0.25 Step 3: Multiply by 100 → 0.25 × 100 = 25% Result: 25% decrease.

What Is Percentage Decrease?

Percentage decrease measures how much a value has fallen relative to its original amount, expressed as a percentage. It is the inverse of percentage increase and is widely used to quantify reductions, discounts, losses, and declines.
  • A price dropping from $100 to $75 is a 25% decrease
  • A stock falling from $200 to $150 is a 25% decrease
  • The original (old) value is always used as the base for the calculation
  • Percentage decrease is always expressed as a positive number by convention

Percentage decrease is commonly used to calculate discounts, track weight loss progress, measure declining sales or revenue, and analyze depreciation of assets over time.

You can also calculate changes using our Percentage Calculator, Percentage Increase Calculator or Discount Calculator.

Frequently Asked Questions

How do I calculate percentage decrease?

Subtract the new value from the old, divide by the old value, and multiply by 100. For example, a drop from 200 to 150 is ((200-150)/200) x 100 = 25% decrease.

What is a good way to express a decrease?

Use phrases like "decreased by 25%" or "dropped 25% from the original value." Avoid saying "decreased by 25% less" as that is a double negative.

Is percentage decrease always positive?

By convention, yes. If the new value is higher than the old, use percentage increase instead. Percentage decrease specifically measures reductions.

How do I calculate a discount percentage?

Use the same formula: ((Original Price - Sale Price) / Original Price) x 100. For example, a $50 item on sale for $35 has a discount of ((50-35)/50) x 100 = 30% off.

Is a 50% decrease the opposite of a 50% increase?

No. A 50% increase on $100 gives $150, but a 50% decrease on $150 gives $75, not $100. To reverse a 50% increase, you need a 33.3% decrease.

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