Percentage Calculator
Calculate any percentage instantly. Find percent of a number, percentage change, or discount savings.
Quick Answer
To find X% of Y, multiply Y by X and divide by 100. Example: 20% of 150 = 150 × 20 ÷ 100 = 30. Use the calculator below for instant results.
Common: 15% of 200 = 30 • 25% of 80 = 20 • 10% of 50 = 5 • 7.5% of 1000 = 75
What is X% of Y?
Enter a percentage and a number to find the result.
More Percentage Tools
How to Calculate Percentages
A percentage is a way of expressing a number as a fraction of 100. The word "percent" comes from the Latin "per centum," meaning "by the hundred." Percentages are used everywhere in daily life: sales discounts, tax rates, tip calculations, grade scores, interest rates, and statistical data.
Three Core Percentage Formulas
Almost every percentage problem can be solved with one of these three formulas:
- Find a percentage of a number: Result = (Percentage / 100) × Number. Example: 25% of 80 = (25/100) × 80 = 20.
- Find what percentage one number is of another: Percentage = (Part / Whole) × 100. Example: 15 is what % of 60? = (15/60) × 100 = 25%.
- Percentage change: Change = ((New - Old) / |Old|) × 100. Example: from 200 to 250 = ((250-200)/200) × 100 = 25% increase.
Why Use a Percentage Calculator?
While the formulas are simple, doing mental math with odd numbers is tedious. How much is 17.5% of $243? That is $42.53, and this calculator gives you the answer instantly. Whether you are shopping for the best deal, calculating a tip, figuring out your grade, or analyzing business metrics, PercentCalc saves you time and eliminates errors.
Common Percentage Calculations
| Question | Formula | Answer |
|---|---|---|
| What is 10% of 100? | 100 × 0.10 | 10 |
| What is 15% of 200? | 200 × 0.15 | 30 |
| What is 20% of 50? | 50 × 0.20 | 10 |
| What is 25% of 80? | 80 × 0.25 | 20 |
| What is 30% of 150? | 150 × 0.30 | 45 |
| What is 50% of 250? | 250 × 0.50 | 125 |
| What is 75% of 400? | 400 × 0.75 | 300 |
Frequently Asked Questions
How do I calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. For example, 20% of 150 = 150 × 20 / 100 = 30. Alternatively, convert the percentage to a decimal (20% = 0.20) and multiply: 0.20 × 150 = 30.
How do I calculate percentage change?
Use the formula: ((New Value - Old Value) / |Old Value|) × 100. A positive result means increase, negative means decrease. Example: from 80 to 100 = ((100-80)/80) × 100 = 25% increase.
What is the formula for discount percentage?
Discount Amount = Original Price × Discount% / 100. Final Price = Original Price - Discount Amount. Example: $120 at 30% off = $120 - $36 = $84.
How do I find what percentage one number is of another?
Divide the part by the whole, then multiply by 100. Formula: (Part / Whole) × 100. Example: 45 out of 200 = (45/200) × 100 = 22.5%.
What is the difference between percentage change and percentage difference?
Percentage change has direction (increase or decrease from a reference value). Percentage difference measures how two values differ relative to their average and has no direction. Change = ((New-Old)/|Old|) × 100. Difference = (|A-B|/((A+B)/2)) × 100.