How is percentage change calculated?

((new − original) ÷ |original|) × 100. From 80 to 100: (20 ÷ 80) × 100 = 25% increase.

What if the original value is zero?

Percentage change from zero is undefined because you cannot divide by zero.

Measure how much a value grew or shrank from A to B. Positive results are increases; negative results are decreases.

Calculate the percent change from A to B

From (original value)

To (new value)

Result

Enter values to calculate

Measure how much a value grew or shrank from A to B. Positive results are increases; negative results are decreases.

Goal	Formula
% change A → B	((B − A) ÷ \|A\|) × 100

How is percentage change calculated?: ((new − original) ÷ |original|) × 100. From 80 to 100: (20 ÷ 80) × 100 = 25% increase.
What if the original value is zero?: Percentage change from zero is undefined because you cannot divide by zero.

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