Three everyday percentage calculations in one place: find X% of a number, work out what percentage one number is of another, and measure the percentage change between two values.
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How to use the Percentage
Use the box for the calculation you need: X% of Y, X is what % of Y, or % change.
Type your numbers into the relevant fields.
Results update instantly as you type.
All three calculators work independently on the same page.
Privacy: this tool runs entirely in your browser. Your input is never sent to, received by, or stored on any server — there are no uploads and no tracking of what you enter.
About Percentage
X% of Y
Multiply to find a portion — e.g. 15% of 200 is 30. Useful for discounts, tips and tax.
X is what % of Y
Divide and scale to express one number as a percentage of another — e.g. 30 is 15% of 200. Useful for scores and progress.
Percentage change
Measure growth or decline: (new − old) ÷ old × 100. A change from 200 to 260 is a 30% increase.
Frequently asked questions
How is percentage change calculated?
As the difference divided by the original value, times 100. Negative results indicate a decrease.
Does it work for discounts and tips?
Yes — "X% of Y" gives the discount or tip amount directly.
Do the calculations update automatically?
Yes, results recalculate as you type in any field.
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