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Percentage Change Calculator

Calculate percent change from an old value to a new value and see whether the result is an increase or decrease.

Result

25%

Mode

Percent change

Formula

(new - old) / |old| x 100

Percentage inputs

Calculate percentages

Calculation mode

Old value

New value

Result details

Answer: 25%
Rounded number: 25
Formula: (new - old) / |old| x 100
Unit: percent

Calculation

Percent change25%

Step(150 - 120) / 120 x 100

Result actions

Next steps

X percent of YUse the dedicated percent-of-number flow for common part calculations.Discount calculatorApply percentage decreases to sale prices and savings.Sales taxAdd or reverse sales tax with percentage inputs.

Percentage Change Calculator formula guide

Percentage queries often look similar, but the formulas differ. This page opens the calculator in the matching mode.

Best use cases

Compare old and new prices, traffic, revenue, grades, or quantities.
Calculate growth rates or declines between two values.
Separate absolute change from percentage change.

Formula guidance

Confirm whether the question is asking for a part of a number, a rate of change, a new value after an increase or decrease, or a percentage-point difference.

Common mistakes

Do not confuse percent change with percentage points.
Use the original value as the base for percent change calculations.
Keep the percent sign separate from decimal form: 25% is 0.25.

Practical examples

These calculations are common in discounts, taxes, finance, grades, conversion rates, analytics changes, margins, and everyday comparison problems.

Frequently asked questions

What is the percent change formula?

Percent change is (new value - old value) / old value x 100.

Can percent change be negative?

Yes. A negative result means the new value is lower than the old value.

What if the old value is zero?

Percent change from zero is undefined because the formula divides by the old value.

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