Percentage Calculator — Every Percentage Calculation in One Tool

Five calculation modes covering every percentage scenario: find X% of a number, calculate what percentage one number is of another, compute percentage change, add a markup, or apply a discount. All instant, all free.

Perfect for calculating discounts while shopping, working out tips, computing tax rates, analysing data changes, or figuring out markups in business.

Free forever No data stored 5 calculation modes

Select calculation type

Calculation mode

Percentage (%)

Value

Enter values above to get your result instantly.

How to Calculate Percentages

A percentage is a fraction expressed as parts per hundred. The word comes from Latin per centum meaning "by the hundred." Percentage calculations appear everywhere — from sales discounts and interest rates to test scores and nutritional labels.

Finding X% of a number

Multiply the number by the percentage divided by 100.

Example: What is 15% of $240?
$240 × 0.15 = $36

Percentage change

Percentage change shows how much a value has increased or decreased relative to its original value.

Formula: ((New − Old) ÷ |Old|) × 100
Example: Price went from $80 to $100: ((100 − 80) ÷ 80) × 100 = +25%

Working out discounts

To find the sale price after a discount: multiply the original price by (1 − discount rate). A 30% discount on $150: $150 × 0.70 = $105.

Percentages are also used in finance for interest rates, in statistics for data analysis, in healthcare for dosage calculations, and in everyday tasks like calculating tips at restaurants (15%, 18%, or 20% of the bill).

Frequently Asked Questions

How do I calculate a percentage of a number?

Divide the percentage by 100, then multiply by the number. Example: 20% of 350 = (20 ÷ 100) × 350 = 0.20 × 350 = 70. Use the "What is X% of Y?" mode above for instant results.

How do I calculate percentage change?

Use the formula: ((New Value − Old Value) ÷ |Old Value|) × 100. A positive result means an increase; a negative result means a decrease. Example: from 200 to 250 = ((250−200)÷200)×100 = 25% increase.

How do I calculate a discount price?

Multiply the original price by (1 − discount ÷ 100). For a 25% discount on $200: $200 × (1 − 0.25) = $200 × 0.75 = $150. Use the "Y minus X% (discount)" mode above.

What is the difference between percentage and percentage points?

Percentage points measure the arithmetic difference between two percentages. If an interest rate goes from 2% to 5%, it increased by 3 percentage points — but by 150% as a relative percentage change. Confusing these two is a very common error in financial reporting.