Percentage Calculator
Percentage Calculator handles the three questions that come up most: what is X% of Y, X is what percent of Y, and the percentage change from one number to another. Each works independently, so you can use whichever you need.
Type your numbers and the answer appears instantly — no formulas to remember.
What is X% of Y?
X is what percent of Y?
Percentage change from X to Y
How to use Percentage Calculator
- 1
Pick the question
Use the block that matches what you want: percent of a number, a ratio, or a change.
- 2
Enter your numbers
Fill in the two values for that block.
- 3
Read the answer
The result updates live as you type.
The three percentage formulas
'X% of Y' multiplies: (X ÷ 100) × Y. For example 20% of 80 is 16.
'X is what percent of Y' divides: (X ÷ Y) × 100. For example 16 is 20% of 80. Percentage change is (new − old) ÷ |old| × 100, which is positive for an increase and negative for a decrease.
Where percentages show up
Percentages are everywhere: tax and tip, discounts, grades, growth rates and statistics. Knowing which of the three formulas applies is usually the only hard part, which is why this tool separates them.
For shopping discounts specifically, a dedicated discount calculator also shows the amount saved and the final price.
Frequently asked questions
- How do I calculate percentage increase?
- Use the 'percentage change' block: enter the old value then the new value. A positive result is an increase, a negative one is a decrease.
- Can it handle decimals?
- Yes. All three blocks accept decimal values and return precise results.
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