Percentage Calculator
Quickly calculate percentages, find what percent one number is of another, or work out percentage changes.
What is X% of Y?
X is what % of Y?
Percentage Change from X to Y
Enter values above to see the result
How to Calculate Percentages
Percentages come up all the time in school and everyday life. Whether you're figuring out your test score, calculating a discount, or working out how much something has changed over time, knowing how to do percentage math is super useful.
The word "percent" just means "per hundred." So 25% is the same as 25 out of 100, or 0.25 as a decimal. Once you remember that, the formulas make a lot more sense. This calculator handles the three most common types of percentage problems you'll run into.
If you got 35 out of 50 on a test and want to know your percentage, just divide 35 by 50 and multiply by 100. That gives you 70%. This calculator does that math for you instantly.
How to Use This Calculator
Pick a Mode
Choose the type of percentage calculation you need using the tabs above the calculator.
Enter Your Numbers
Type in the values and the result updates in real-time. No buttons to click.
Copy or Swap
Copy the result to your clipboard, swap the input values, or clear and start over.
Common Percentage Formulas
| Calculation | Formula | Example |
|---|---|---|
| What is X% of Y? | (X / 100) x Y | 25% of 200 = 50 |
| X is what % of Y? | (X / Y) x 100 | 35 is 70% of 50 |
| Change from X to Y | ((Y - X) / |X|) x 100 | 80 to 100 = 25% increase |
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