Percentage Calculator

Work out a percentage of a number, a percentage increase or decrease, or a reverse percentage, with each step shown. Ask something like “what is 18% of 250?” and see exactly how the answer is built.

Try an example:

What you can do with the Percentage Calculator

Percent-of, percent change, increase, decrease and reverse percentages.

Enter your values or describe the problem in the calculator above. Review the result and the explanation before using it in homework, study or practical calculations.

Example input

Enter a percent question, such as what is 18% of 250?

How the Percentage Calculator works

  1. Turn the percent into a decimal or fraction (18% = 0.18 = 18/100).
  2. Multiply it by the number, or use (new − old) ÷ old × 100 for percent change.
  3. Check that the result makes sense: 18% of 250 should be a bit under a fifth of 250.

Frequently asked questions

How do I calculate a percentage of a number?

Divide the percentage by 100 and multiply by the number. For 18% of 250 that is 0.18 × 250 = 45.

How do I find percentage change?

Subtract the old value from the new one, divide by the old value, then multiply by 100. A positive result is an increase, a negative one a decrease.

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Math Solver can make mistakes. Please double-check important steps and calculations.