How to use it
- Choose the calculation you need.
- Enter the two numbers, including decimals or zero where valid.
- Calculate and copy the result with its formula.
Percentage change is not a percentage-point change
- Input
- Original value: 80; new value: 100; mode: percentage change
- Result
- 25% increase
The increase is 20, divided by the original 80, then multiplied by 100. Reversing the values gives a 20% decrease. A change from zero has no finite percentage-change result.
Useful situations
- Work out a discount or a grade percentage.
- Compare an old and a new measurement.
Limits and supported formats
A percentage ratio needs a nonzero denominator. Percentage change from zero is undefined. Results use browser floating-point arithmetic, not financial settlement rules.
Privacy
We do not store tool content or results. Optional usage events do not include files, filenames, text, passwords or QR contents. Reset when finished and save any output you need on your own device.
Questions about this tool
Is a change from 10 to 20 an increase of 10%?
The absolute increase is 10; the percentage increase is 100%, measured against the starting value.
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