How do I find percentage change?

Subtract the old value from the new value, divide by the old value, and multiply by 100.

Yes. Processing happens in your browser. Nothing you enter is sent to our servers.

Yes. It is free, with no sign-up or usage limit.

Home › Calculators › Percentage Calculator

Percentage Calculator – Free Online Tool

Quick answer: Calculate percent of a number, what percent one number is of another, and percentage change.

About this tool

Three calculators in one: X percent of Y, X is what percent of Y, and percentage increase or decrease.

How to use the Percentage Calculator

Enter your text, choose your file or set the options in the tool above.
Click the action button for the result you want.
Copy or download the output. Nothing leaves your device.

The three calculations explained

X% of Y: multiply Y by X and divide by 100. Example: 20% of 500 is 100.
X is what % of Y: divide X by Y and multiply by 100. Example: 50 is 25% of 200.
Percentage change: subtract the old value from the new value, divide by the old value and multiply by 100. Example: from 80 to 100 is a 25% increase.

Everyday uses

Discounts: a 4,000 item with 15% off saves 600, so you pay 3,400.
Tax and fees: work out the amount added to a price.
Marks and grades: turn 412 out of 500 into a percentage.
Salary and prices: see how much a raise or price rise really is.

Common mistakes

Percentage change is always measured against the old value, so swapping the two numbers gives a different answer. An increase of 20% followed by a decrease of 20% does not bring you back: 100 becomes 120, then 96. Also remember that percentage points and percent are different: moving from 10% to 12% is 2 percentage points but a 20% increase.

All three calculators update as you type, with no button to press. For loans and interest, use the Loan EMI Calculator.

Why use ToolWorlds?

Free, with no registration
Private: runs in your browser
Works on phones, tablets and desktops

Frequently asked questions

How do I find percentage change?: Subtract the old value from the new value, divide by the old value, and multiply by 100.
Is my data safe?: Yes. Processing happens in your browser. Nothing you enter is sent to our servers.
Is it free?: Yes. It is free, with no sign-up or usage limit.

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