Percentage Calculator

What is a Percentage Calculator?

A Percentage Calculator solves the three most common percentage operations on one screen. Switch tabs to compute a percentage of a number, the percentage change between two values, or a part of a whole as a ratio. All results update instantly as you type.

Which operations are included?

• Percentage of a number: enter a number and a rate; e.g. 20% of 100 is 20.
• Percentage change: enter start and end values; e.g. going from 80 to 100 is a 25% increase.
• Percentage of a whole: see what share a part represents; e.g. 20 is 20% of 100.

Where is it used?

Shopping to calculate discounts and price increases, education to read exam pass rates and surveys, business to track sales and profit changes, and daily budgeting to plan allocations. Decimal values are supported.

About the tool

Calculations run entirely in your browser; your inputs are never sent or stored, no signup or install is needed. In Change mode, increases and decreases are color coded so you interpret the result correctly at a glance.