Percentage Calculator

Math guide

How to use the Percentage Calculator

Solve common percentage questions, including percent of a number and percentage change. The page also explains the percentage formulas and shows a practical example: 15% of 240 is 240 x 15 / 100 = 36. A change from 80 to 100 is 25%.

  1. 1

    Enter your details

    Enter the values for the percentage calculator scenario you want to check.

  2. 2

    Check the calculation

    Review the result alongside the percentage formulas: Percent of number = number x percent / 100; change % = (new - old) / old x 100.

  3. 3

    Compare scenarios

    Change one or more inputs to see how they affect the percentage Calculator result before you use the estimate.