Percentage Calculator
Calculate percentages, find what percentage one number is of another, and calculate percentage increase or decrease quickly and easily.
Percentage Calculator
Choose a calculation below and enter your values.
What is X% of Y?
Find a percentage of a number.
Result
Enter your values to calculate the result.
X is What % of Y?
Find what percentage one number represents of another number.
Result
Enter your values to calculate the result.
Percentage Increase or Decrease
Calculate the percentage change between an original value and a new value.
Result
Enter your values to calculate the result.
What Is a Percentage?
A percentage is a way of expressing a number as a fraction of 100. The word percentage means "per hundred," and the symbol % is used to represent it.
Percentages are commonly used for discounts, price changes, grades, statistics, financial calculations, taxes, interest, business reports, and everyday comparisons.
This Percentage Calculator provides three common calculations: finding a percentage of a number, finding what percentage one number is of another, and calculating percentage increase or decrease.
Percentage Formula
The basic percentage formula is:
For example, if you have 25 out of 100:
How to Use This Percentage Calculator
1. Calculate X% of Y
Enter the percentage and the number. The calculator multiplies the percentage by the number and divides the result by 100.
2. Find What Percentage X Is of Y
Enter the part and the whole. The calculator divides the part by the whole and multiplies the result by 100.
3. Calculate Percentage Increase or Decrease
Enter the original value and the new value. The calculator determines the percentage change between them.
Common Percentage Calculations
| Calculation | Formula | Example |
|---|---|---|
| Percentage of a number | (X × Y) ÷ 100 | 20% of 150 = 30 |
| What percentage? | (Part ÷ Whole) × 100 | 30 of 150 = 20% |
| Percentage increase | ((New − Original) ÷ Original) × 100 | 100 to 125 = 25% |
| Percentage decrease | ((Original − New) ÷ Original) × 100 | 100 to 75 = 25% |
Percentage Examples
Example 1: What is 20% of 150?
Multiply 20 by 150 and divide by 100.
Example 2: 30 is what percentage of 150?
Divide 30 by 150 and multiply by 100.
Example 3: A price increases from $100 to $125
The increase is $25. Divide $25 by the original $100 and multiply by 100.
Example 4: A price decreases from $100 to $75
The decrease is $25. Divide $25 by the original $100 and multiply by 100.
Percentage Increase vs Percentage Decrease
| Type | What Happens | Formula |
|---|---|---|
| Increase | New value is greater than original value | ((New − Original) ÷ Original) × 100 |
| Decrease | New value is lower than original value | ((Original − New) ÷ Original) × 100 |
Percentage, Decimal, and Fraction
| Percentage | Decimal | Fraction |
|---|---|---|
| 10% | 0.10 | 1/10 |
| 20% | 0.20 | 1/5 |
| 25% | 0.25 | 1/4 |
| 50% | 0.50 | 1/2 |
| 75% | 0.75 | 3/4 |
| 100% | 1.00 | 1 |
Reverse Percentage Calculations
Sometimes you know the final amount and the percentage, but need to find the original amount.
Finding the Original Value After an Increase
Finding the Original Value After a Decrease
These formulas can be useful for working backward from discounted prices, increased prices, or other percentage-based changes.
Real-World Uses of Percentages
- Shopping discounts and sale prices
- Tax and other charges
- Investment returns
- Loan interest
- Business growth and revenue changes
- Exam scores and grades
- Statistics and data analysis
- Budgeting and personal finance
- Comparing prices and quantities
Common Percentage Mistakes
- Using the wrong reference value when calculating percentage change.
- Forgetting to divide by 100 when calculating a percentage of a number.
- Confusing percentage change with the difference between two percentages.
- Using the new value instead of the original value as the reference when calculating a percentage increase or decrease.
- Assuming a percentage increase and the same percentage decrease cancel each other out.
Percentage vs Percentage Points
Percentage and percentage points describe different things.
For example, if an interest rate changes from 5% to 7%, the difference is 2 percentage points.
The relative percentage increase, however, is:
Therefore, the rate increased by 2 percentage points, which is a 40% relative increase.
Frequently Asked Questions
What is a percentage?
A percentage expresses a number as a fraction of 100.
How do I calculate X% of a number?
Multiply the percentage by the number and divide by 100. For example, 20% of 150 is 30.
How do I find what percentage one number is of another?
Divide the part by the whole and multiply by 100.
How do I calculate percentage increase?
Subtract the original value from the new value, divide by the original value, and multiply by 100.
How do I calculate percentage decrease?
Subtract the new value from the original value, divide by the original value, and multiply by 100.
Can a percentage be greater than 100%?
Yes. A percentage can be greater than 100% when the value being compared is greater than the reference value.
What is the difference between percentage and percentage points?
Percentage points describe the arithmetic difference between two percentage values, while percentage change describes the relative change.
Is this Percentage Calculator free?
Yes. CalclyWorld calculators are free to use.
Does the Percentage Calculator work on mobile?
Yes. The calculator is designed to work on smartphones, tablets, and desktop computers.
What is the difference between this calculator and the Percentage Increase Calculator?
This calculator provides several common percentage calculations. The dedicated Percentage Increase Calculator focuses specifically on percentage increases.
What is the difference between this calculator and the Percentage Decrease Calculator?
This calculator provides several common percentage calculations. The dedicated Percentage Decrease Calculator focuses specifically on percentage decreases.
Disclaimer
CalclyWorld calculators are provided for general informational and educational purposes. Results may vary depending on the assumptions and values entered. Always verify important financial, tax, legal, or business calculations with an appropriate professional or authoritative source.