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Percentage Change Calculator

Calculate the percentage increase or decrease between two numbers, plus the percentage difference. Free calculator for prices, salaries, grades and stats.

Percentage increase
+25%
Change
+20
Percentage difference
22.2222%
Multiplier
× 1.25

Increase, decrease and difference

Percentage change compares a new value with a starting value: subtract the old value from the new one, divide by the old value and multiply by 100. A price rising from 80 to 100 is a 25% increase; falling from 100 to 80 is a 20% decrease. The order matters. Percentage difference is different: it compares two values without either being the starting point, dividing the gap by their average. Use it when comparing two shops, two products or two measurements.

How to use it

  1. 1

    Enter the starting value

    The old price, last year's figure or the original measurement.

  2. 2

    Enter the final value

    The new price or this year's figure.

  3. 3

    Read the change

    See the percentage increase or decrease, the change itself and the percentage difference.

Frequently asked questions

What's the formula for percentage increase?

(New − Old) ÷ Old × 100. From 50 to 65: (65 − 50) ÷ 50 × 100 = 30% increase.

Why isn't a 20% drop undone by a 20% rise?

Because each percentage is taken from a different starting value. 100 minus 20% is 80, but 80 plus 20% is only 96. To get back to 100 you need a 25% increase.

When should I use percentage difference?

When neither value is the 'before' value, such as comparing the price of the same item in two stores.

Is anything sent to a server?

No. Everything is calculated in your browser, and nothing you type is stored or sent anywhere.

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