What is the difference between percentage decrease and percentage change?

Percentage change can be either positive (an increase) or negative (a decrease). Percentage decrease specifically measures how much a value has fallen as a proportion of the original, and is expressed as a positive number (e.g. '25% decrease' rather than '-25% change'). Use this calculator when you know the value has gone down and you want to express that fall as a percentage.

How do I find the new value after a percentage decrease?

New value = Original value x (1 - Percentage decrease / 100). For example, a 20% decrease from 500 gives 500 x (1 - 0.20) = 500 x 0.80 = 400. This calculator lets you enter either the new value directly or a known percentage decrease to find the new value.

Percentage Decrease Calculator

Find the percentage decrease between two numbers. Enter the original value and the new (lower) value to see the percentage decrease, the amount of decrease, and a worked breakdown.

You can also enter a known percentage decrease to find the resulting new value.

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Standard formula Percentage decrease = ((Original − New) / Original) × 100

1. Calculate Percentage Decrease

Original value

Please enter a valid number greater than zero.

New (lower) value

Please enter a valid number.

2. Or Find New Value from % Decrease

Original value (for reverse lookup)

Percentage decrease

Enter a percentage between 0 and 100.

Results

Percentage Decrease
25%
How much it fell

Decrease Amount

Original minus New

New Value (from %)

150

After applying % decrease

Percentage Decrease Breakdown

Original value200

New value150

Decrease amount50

Decrease / Original50 / 200 = 0.25

Percentage decrease25.00%

Reverse Lookup Breakdown

Original value200

Percentage decrease25%

Multiplier1 − 0.25 = 0.75

Calculation200 × 0.75

New value150

Summary: 200 decreased by 25% gives a new value of 150. The decrease amount is 50.

How to Calculate Percentage Decrease

The percentage decrease formula measures how much a value has fallen relative to its starting point. The calculation has two steps:

Find the decrease amount: Decrease = Original value − New value
Divide by the original and multiply by 100: Percentage decrease = (Decrease / Original) × 100

For example, if a product's price drops from $200 to $150, the decrease is $50, and the percentage decrease is (50 / 200) × 100 = 25%.

Formula

What you want to find	Formula
Percentage decrease	((Original − New) / Original) × 100
Decrease amount	Original − New
New value from % decrease	Original × (1 − Percentage / 100)
Original from new value and %	New value / (1 − Percentage / 100)

Worked Example

A jacket was priced at $200. It is now on sale for $150. What is the percentage decrease?

Decrease amount: $200 − $150 = $50
Percentage decrease: ($50 / $200) × 100 = 25%

The jacket has decreased in price by 25%. To verify the reverse: $200 × (1 − 0.25) = $200 × 0.75 = $150.

Common Uses

Shopping and sales: Working out the actual percentage off a sale price.
Finance and investing: Measuring a portfolio or asset's fall in value.
Statistics and data: Comparing figures across time periods (e.g. year-on-year revenue falls).
Science: Reporting the reduction in a measured quantity between experiments.
Health and fitness: Tracking weight loss or reductions in measurements.

Percentage Decrease vs Percentage Change

Percentage change can be positive (an increase) or negative (a decrease). Percentage decrease is always expressed as a positive number showing how far a value has fallen. For example, a change from 200 to 150 is a percentage change of −25% or a percentage decrease of 25%. Use the Percentage Change Calculator if you are not sure whether the value has risen or fallen.

Related Calculators

Maths and Stats Calculators: all percentage and number tools.
Percentage Increase Calculator: find the percentage rise between two values.
Percentage Change Calculator: handles both increases and decreases.
Percentage Difference Calculator: compare two values without a clear direction.
Percentage Calculator: general-purpose percentage tool.

Method: Standard percentage decrease formula: ((Original − New) / Original) × 100. Reverse calculation: Original × (1 − Percentage / 100). No rounding is applied until display.

This calculator is for general mathematical use. Results are based on the values you enter. Verify calculations independently for financial, scientific, or academic purposes.

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