Percentage Calculator

Calculate percentages, percentage change, increases, decreases, discounts, and more with our free online Percentage Calculator.

Choose a calculation

What is X% of Y?

Find a percentage of any number quickly and accurately.

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X is what percent of Y?

Find what percentage one value represents of another value.

X is Y% of what?

Find the original number when you know a percentage and its value.

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Percentage Increase

Measure how much a value increased compared with its original value.

Percentage Decrease

Measure how much a value decreased compared with its original value.

Percentage Change

Compare a new value with its original value and identify the increase or decrease.

Discount Calculator

Calculate savings and the final price after a percentage discount.

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Percentage Difference

Compare two values when neither one is treated as the starting or reference value.

Your Result

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Enter your values to calculate a percentage.

Quick Examples

Try a ready-made calculation for the selected mode.

Your calculations are performed directly in your browser. No values are sent to our servers.

What Is a Percentage?

A percentage represents a number as a fraction of 100. For example, 25% means 25 out of every 100. Percentages make it easier to describe proportions, changes, comparisons, and rates in a simple format.

Percentages are commonly used for discounts, price changes, statistics, finance, grades, business calculations, measurements, and comparing values.

How to Calculate a Percentage

To calculate a percentage of a number, convert the percentage to a decimal and multiply it by the number.

Result = (Percentage ÷ 100) × Number

For example, to calculate 20% of 150:

20% of 150 = (20 ÷ 100) × 150 = 30

Percentage Formula

The basic percentage formula is useful whenever you need to calculate a percentage of a number.

Result = (Percentage ÷ 100) × Number

You can also rearrange percentage formulas to find the percentage itself or find the original value when the percentage and result are known.

How to Calculate Percentage Increase

Percentage increase tells you how much a value has increased relative to its original value.

Percentage Increase = ((New Value − Original Value) ÷ Original Value) × 100

For example, if a value changes from 100 to 125, the increase is 25. Dividing 25 by 100 and multiplying by 100 gives a 25% increase.

How to Calculate Percentage Decrease

Percentage decrease shows how much a value has fallen compared with its original value.

Percentage Decrease = ((Original Value − New Value) ÷ Original Value) × 100

If a value changes from 200 to 150, the decrease is 50. Since 50 is one quarter of 200, the percentage decrease is 25%.

How to Calculate Percentage Change

Percentage change measures how much a value has changed relative to its original value. The signed result can be positive or negative.

Percentage Change = ((New Value − Original Value) ÷ Original Value) × 100

A positive result represents an increase, while a negative result represents a decrease. For example, changing from 100 to 120 gives a 20% increase.

How to Calculate a Discount

A discount reduces an original price by a specified percentage. First calculate the discount amount, then subtract it from the original price.

Discount Amount = Original Price × Discount Percentage ÷ 100
Final Price = Original Price − Discount Amount

For example, a 20% discount on 100 gives a discount amount of 20 and a final price of 80.

Percentage Difference vs Percentage Change

Percentage change treats one value as the starting or reference value. Percentage difference is used when neither value should be treated as the starting value.

Percentage Difference = |A − B| ÷ ((A + B) ÷ 2) × 100

For example, 100 and 120 have an absolute difference of 20 and an average of 110. Their percentage difference is therefore approximately 18.18%.

Percentage Calculation Examples

Percentage of a Number

20% of 150 = 30.

What Percentage Is One Number of Another?

30 is 20% of 150.

Percentage Increase

100 → 125 = 25% increase.

Percentage Decrease

200 → 150 = 25% decrease.

Discount

100 with a 20% discount = 80.

Percentage Difference

100 and 120 have a percentage difference of 18.18%.

How to Use the Percentage Calculator

1 Choose a calculation Select the percentage calculation that matches your question.
2 Enter your values Enter the required numbers. Decimal values are supported.
3 Calculate Click Calculate or enter values to see the live result.
4 Review the result Read the main result and supporting statistics.
5 Copy the result Use Copy Results to create a clean plain-text summary.
6 Start again Use Reset whenever you want to begin a new calculation.

Frequently Asked Questions

A percentage is a way of expressing a number as a fraction of 100. For example, 25% means 25 out of 100.

Multiply the number by the percentage divided by 100. For example, 20% of 150 is (20 ÷ 100) × 150 = 30.

Divide the first number by the second number and multiply by 100. For example, 30 ÷ 150 × 100 = 20%.

Subtract the original value from the new value, divide the difference by the original value, and multiply by 100.

Subtract the new value from the original value, divide by the original value, and multiply by 100.

Use ((New − Original) ÷ Original) × 100. A positive result means an increase and a negative result means a decrease.

Multiply the original price by the discount percentage divided by 100. Then subtract the discount amount from the original price to find the final price.

Percentage change uses one value as the starting point. Percentage difference compares two values without treating either one as the starting value.

Yes. The calculator supports decimal values and keeps full precision during calculations before formatting the displayed result.

Yes. The Percentage Calculator is free to use, and calculations are performed directly in your browser without sending your values to a server.