Percentage Calculator
Calculate percentages instantly with four different calculation modes. Find what percent of a number, percentage change, increase or decrease, and more.
What is X% of Y?
How to Use This Percentage Calculator
Our free percentage calculator provides four common calculation modes so you can solve any percentage problem quickly. All calculations happen instantly in your browser -- nothing is sent to a server.
Calculation Modes
- X% of Y -- Find a percentage of a number. For example, "What is 25% of 200?" Answer: 50.
- X is what % of Y -- Determine what percentage one number is of another. For example, "50 is what percent of 200?" Answer: 25%.
- % Change -- Calculate the percentage increase or decrease between two values. For example, from 100 to 150 is a 50% increase.
- Increase / Decrease -- Increase or decrease a number by a given percentage. For example, 200 increased by 15% equals 230.
Tips
Use the tabs at the top of the calculator to switch between modes. Each mode has its own inputs and a dedicated calculate button. Click "Clear" to reset the inputs and start a new calculation.
Frequently Asked Questions
How do I calculate a percentage of a number?
To find X% of Y, multiply Y by X and divide by 100. For example, 25% of 200 = (200 x 25) / 100 = 50. Use our "X% of Y" tab for instant results.
How do I calculate percentage change?
Percentage change is calculated as ((New Value - Old Value) / |Old Value|) x 100. A positive result indicates an increase, while a negative result indicates a decrease.
What is the difference between percentage increase and percentage change?
They use the same formula. "Percentage change" is the general term that covers both increases and decreases. A "percentage increase" specifically refers to a positive change, while a "percentage decrease" refers to a negative change.
Can I calculate percentages with decimals?
Yes. All input fields accept decimal values. You can enter values like 12.5% or 99.99 in any field and the calculator will handle them correctly.
Why does percentage change use the absolute value of the original number?
Using the absolute value of the original number ensures meaningful results when the starting value is negative. For example, a change from -50 to -25 is a 50% change (the value moved 50% closer to zero).