Percentage Calculator
Work out a percentage of a number, one number as a percentage of another, or a percentage change.
1 min read
Runs in your browser — your text and files never leave your device.
Three everyday percentage questions in one place: discounts and tips, proportions, and how much something went up or down.
How to use it
- Choose the question you are answering.
- Enter both numbers.
- Press Calculate, then copy the result.
Good to know
- A percentage change from zero has no answer, so the calculator says so instead of returning infinity.
- Results are shown with up to eight significant digits and no thousands separators, so they paste cleanly into a spreadsheet.
Related tools: Date Calculator · Unit Converter
Frequently asked questions
How do I work out a discount?
Use "What is X% of Y?" with the discount as X. A 25% discount on 80 is 20 — that is the amount off, which you subtract from the original price.
Why can I not calculate a percentage change from zero?
Going from zero to anything is an increase of infinitely many percent, so the answer is undefined rather than a number.