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Percentage Calculator

Five common percentage problems, solved as you type.

About this percentage calculator

Percentages describe a part out of 100. To find X percent of Y, multiply Y by X and divide by 100. To find what percent X is of Y, divide X by Y and multiply by 100. Percentage change is the new value minus the old value, divided by the absolute old value, times 100. Use the increase and decrease card for discounts, price rises and tips, and the last card to work backwards to the original number.

How to use it

  1. Pick the card that matches your question.
  2. Fill in the two numbers.
  3. The answer appears as you type, and you can copy it.

Frequently asked questions

What is the difference between percent and percentage points?

Moving from 10% to 12% is a rise of 2 percentage points, but a 20% increase relative to the starting value.

Why does a 20% rise then a 20% fall not return to the start?

The second change applies to a larger number, so you end up 4% lower.