A percentage calculator is a tool used to perform mathematical operations involving percentages. The main purpose of a percentage calculator is to calculate the percentage of a given number. This is done by dividing the number by another number and multiplying the result by 100. The resulting value represents the percentage of the original number.

For example, if you want to find 20% of 50, you would divide 50 by 100 and then multiply the result by 20. The answer would be 10, which represents 20% of 50.

Percentage calculators are widely used in various fields, such as finance, education, and retail. They can be in the form of physical devices, or they can be digital tools, such as online calculators or smartphone apps. These tools are often used to perform quick and accurate calculations, especially when working with large numbers.