Math Tools
Percentage Calculator
Calculate percentages, find a percent of a number, and measure percentage increase or decrease.
Percentage Calculator
Calculate percentages, percentage of a number, and percentage change quickly and clearly.
Find what percent one number is of another.
Result
25%
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A compact calculator can be useful for quick percentages, discounts, taxes, homework, finance, and everyday calculations.
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Included calculations
This calculator can find what percent one number is of another, compute a percentage of a value, and show percentage increase or decrease.
What is a percentage calculator?
A percentage calculator is a fast way to solve common percent problems without doing the arithmetic manually. It can help you find what percent one number is of another, calculate a percent of a value, and measure percentage increase or percentage decrease.
This is useful for school math, exam scores, discounts, tax calculations, profit margins, price changes, statistics, budgeting, and many everyday percentage questions.
Percentage formulas
What percent is X of Y?
Percentage = (part ÷ whole) × 100
What is X% of Y?
Result = (percent ÷ 100) × value
Percentage change formula
((new value - original value) ÷ original value) × 100
What percent is X of Y? examples
These worked examples match the selected percentage calculation type.
Current formula
Percentage = (part ÷ whole) × 100
| Example | Answer |
|---|---|
| 25 is what percent of 100? | 25% |
| 18 is what percent of 60? | 30% |
| 45 is what percent of 90? | 50% |
Quick percentage reference table
This quick table shows common percentages converted into decimals and simple fractions, which is useful when doing mental math or checking percentage calculations.
| Percentage | Decimal | Simple meaning |
|---|---|---|
| 1% | 0.01 | 1 out of 100 |
| 5% | 0.05 | 5 out of 100 |
| 10% | 0.10 | 10 out of 100 |
| 25% | 0.25 | One quarter |
| 50% | 0.50 | One half |
| 75% | 0.75 | Three quarters |
| 100% | 1.00 | The full amount |
How to calculate percentages step by step
To find what percent one number is of another, divide the part by the whole and multiply by 100. For example, if 25 is compared to 100, the result is 25%.
To calculate a percentage of a number, turn the percent into a decimal and multiply. For example, 20% of 50 equals 0.20 × 50, which gives 10.
To calculate percentage increase or decrease, subtract the original value from the new value, divide by the original value, and multiply by 100. Positive results mean an increase, while negative results mean a decrease.
Percentage increase and percentage decrease explained
Percentage increase shows how much a value has gone up relative to the original amount. For example, if a price rises from 80 to 100, the percentage increase is 25%.
Percentage decrease shows how much a value has dropped relative to the original amount. For example, if a price falls from 200 to 150, the percentage decrease is 25%.
This kind of percentage change calculation is useful in finance, sales reports, stock tracking, population studies, and performance analysis.
Where a percentage calculator is useful
A percentage calculator is useful when calculating discounts, exam results, taxes, tips, commission, profit margins, growth rates, and price changes. It can also help with comparing values in reports and understanding business or finance data.
Students use percentage calculators for math homework and exam revision, while professionals may use them for accounting, sales, payroll, and budgeting tasks.
Percentage calculator FAQ for common percentage questions
How do I calculate what percent one number is of another?
Divide the part by the whole and multiply by 100. For example, 25 divided by 100 equals 0.25, which becomes 25%.
How do I calculate a percentage of a number?
Convert the percent to a decimal and multiply it by the value. For example, 15% of 200 equals 30.
What is the formula for percentage increase?
Subtract the original value from the new value, divide by the original value, and multiply by 100.
What is the formula for percentage decrease?
Subtract the new value from the original value, divide by the original value, and multiply by 100. This gives the size of the decrease as a percentage of the original value.
Can this calculator show both increase and decrease?
Yes. The percentage change mode can show a positive result for an increase or a negative result for a decrease.
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