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Percentage Calculator

Work out a percentage of a number, a percentage change, or add and subtract a percentage. Clear sentences, free, and private in your browser.

Result

Type two numbers to see the answer.

Shortcuts: Ctrl+Enter run · Ctrl+Shift+C copy result · / search (use ⌘ on Mac)

Next steps

Done here? Use the Send to… menu on the result to carry it on to Scientific Calculator or Loan Calculator.

Free Online Percentage Calculator

Find a percentage of a number, see how much something went up or down, or add and subtract a percentage. Type two numbers and the answer appears with a sentence you can copy. Work out what a percentage of a number is, how much something changed in percent, or what a price is after a discount or tax. The answer is written as a plain sentence so you can check it.

How to use the percentage calculator

Pick what you want to know, then fill in the two boxes. The answer updates as you type. Use the swap button if you typed the numbers the wrong way round.

Five things it can work out

  • X% of Y: for example 15% of 80 is 12.
  • X is what % of Y: for example 25 is 12.5% of 200.
  • Change from X to Y: the percentage increase or decrease between two values.
  • Add or subtract X% to Y: for example 150 plus 20% is 180.
  • Y is X% of what: finds the whole from a part.

Common mistakes

  • Mixing up the starting value and the new value in a change: the percentage depends on which one is first.
  • Taking 20% off and then adding 20% back: you do not return to the start, because the second 20% is of a smaller number.

Frequently asked questions

How do I work out a percentage of a number?
Choose "X% of Y", type the percentage and the number. For 15% of 80 the answer is 12, because 15 divided by 100 is 0.15 and 0.15 times 80 is 12.
How is the percentage change worked out?
The calculator takes the new value minus the starting value and divides by the starting value. Going from 80 to 100 is an increase of 25%. Going from 100 back to 80 is a decrease of 20%, which is why the two are not the same.
What does the "reverse" mode do?
It finds the whole when you know a part. If 30 is 15% of a number, the number is 200. It is useful for finding a price before a discount or tax.
Why can it not divide by zero?
A percentage of 0 or a change from 0 has no meaning, so the calculator tells you which box to change instead of showing a wrong answer.
How do I take 20% off a price?
Use the add or subtract mode: type the price and 20 and choose subtract. For 80 the answer is 64, because 20% of 80 is 16.

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