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Math

Percentage Change Calculator

Instantly find the % increase or decrease between any two numbers

Enter Two Values

Quick examples:

Result

Percentage Increase +25%
Original value80
New value100
Absolute difference+20
Percentage change+25%

Formula used

((10080) ÷ |80|) × 100 = +25%

How It Works

Formula

((New − Old) ÷ |Old|) × 100

Increase example

80 → 100: ((100 − 80) ÷ 80) × 100 = +25%

Decrease example

120 → 90: ((90 − 120) ÷ 120) × 100 = −25%

About

The Percentage Change Calculator finds the exact percent increase or decrease between any two numbers in seconds. Whether you are tracking a price drop, salary raise, stock movement, or test score improvement, just enter the original and new values to see the percentage change, absolute difference, and the formula used — no manual math required.

FAQ
What is the formula for percentage change?+

Percentage change = ((New Value − Original Value) ÷ |Original Value|) × 100. A positive result means an increase; a negative result means a decrease.

What is the difference between percentage change and percentage difference?+

Percentage change compares a new value to a specific starting (original) value — it has a clear direction (increase or decrease). Percentage difference compares two values symmetrically with no defined starting point, using their average as the denominator.

Can the original value be zero?+

No. Division by zero is mathematically undefined, so a starting value of zero makes percentage change impossible to calculate. The calculator will display a friendly error if you enter zero as the original value.

How do I calculate a percentage decrease?+

Use the same formula: ((New − Original) ÷ |Original|) × 100. If the new value is smaller than the original, the result will be negative, indicating a decrease. For example, 120 → 90 gives ((90−120) ÷ 120) × 100 = −25%.

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