Percentage Calculator
What is Percentage Calculator
A percentage calculator solves the three most common percentage problems: finding a percentage of a number, finding what percentage one number is of another, and calculating percentage increase or decrease between two numbers.
How to use
- Select the calculation mode with the tabs at the top.
- Mode 1: Enter X and Y to find what X% of Y is.
- Mode 2: Enter X and Y to find what percentage X is of Y.
- Mode 3: Enter the original and new value to find the percentage change.
- Results update in real time as you type.
When to use it
Spotted 30% off a $120 item and want the real price? Mode 1 tells you the discount is $36 and the final price is $84. And when your salary goes from $50,000 to $55,000, Mode 3 confirms that is a 10% raise, so you always know exactly where the numbers land.
Frequently asked questions
How do I calculate X% of Y?
Use Mode 1. Enter the percentage (X) and the number (Y). The result is X ÷ 100 × Y.
How do I find what percentage X is of Y?
Use Mode 2. Enter X and Y. The result is (X ÷ Y) × 100.
How is percentage change calculated?
Percentage change = ((New Value − Original Value) ÷ |Original Value|) × 100. A positive result is an increase, negative is a decrease.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you type. Copy it from the address bar or use the Share button — anyone who opens the link will see your exact inputs ready to go.
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