Free Percentage Calculator

What Is a Percentage Calculator?

A percentage calculator is a free multi-mode online tool that handles the four most common percentage calculations in everyday life: finding what X% of a number is, determining what percentage one number is of another, calculating the percentage change between two values, and finding a new value after applying a percentage increase or decrease. Whether you are working out a tip, a discount, a test score or a pay rise, this tool gives you the answer instantly with the full working formula shown.

Percentage calculations appear in virtually every area of daily life — finance, shopping, school grades, health metrics and data analysis. Our calculator eliminates mental arithmetic errors by handling all four scenarios with clear labelled inputs, showing the formula used so you can learn and verify the result.

How to Use the Percentage Calculator - Step by Step

1. 1

   Choose a calculation mode

   Select one of the four tabs: 'X% of Y', 'X is what % of Y', '% Change', or 'Apply %'. Each mode has its own clearly labelled inputs.

2. 2

   Enter your numbers

   Type the values into the input fields. Commas are ignored so you can paste large numbers freely.

3. 3

   Click Calculate

   Get your answer instantly with the full arithmetic formula displayed so you can verify and learn the working.

Frequently Asked Questions - Percentage Calculator

How do I calculate 20% of 500?

Use the 'What is X% of Y?' mode. Enter 20 as X and 500 as Y. The result is (20 ÷ 100) × 500 = 100.

How do I find what percentage 80 is of 200?

Use the 'X is what % of Y?' mode. Enter 80 as X and 200 as Y. The result is (80 ÷ 200) × 100 = 40%.

How do I calculate percentage increase from 100 to 150?

Use the '% Change' mode. Enter 100 as the original value and 150 as the new value. The result is ((150 − 100) ÷ 100) × 100 = 50% increase.

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