Percentage Calculator
Calculate percentages, discounts, increases and decreases quickly with clear formulas.
Free online percentage calculator
Calculate the percentage of a number, what percentage one value represents of another, and the percentage increase or decrease between two amounts. Ideal for discounts, taxes, statistics and personal finance.
Percentage formulas
- X% of Y: (X ÷ 100) × Y — what is 15% of 200 (30).
- What percentage: X ÷ Y × 100 — what % is 30 of 200 (15%).
- Percentage change: (Y − X) ÷ X × 100 — went from 80 to 100: +25%.
How to use the percentage calculator
- Choose the mode you need: "What is X% of Y?", "X is what % of Y?" or "Increase / Decrease".
- Enter both values in the X and Y fields.
- Read the result instantly, along with the formula used so you can verify it.
Percentage examples in everyday life
- Discounts: a 30% discount on a $20 product means paying $6 less.
- Taxes: if a final price includes 19% VAT, you can calculate how much corresponds to tax.
- Tips: 10% or 15% of a restaurant bill uses the same formula.
- Finance: interest, inflation, sales growth and margins are all expressed as percentages.
Frequently Asked Questions
How do you calculate a percentage of a number?
Multiply the number by the percentage and divide by 100. Example: 15% of 200 is (15 × 200) ÷ 100 = 30.
How do I calculate the discount percentage of a product?
Divide the discount amount by the original price and multiply by 100. If something costs $40,000 and you pay $32,000, the discount was 20%.
What is percentage change?
It measures how much a value increased or decreased: (final value − initial value) ÷ initial value × 100. Going from 80 to 100 is a 25% increase.
Is this percentage calculator free?
Yes, it is 100% free, no registration needed, and it runs directly in your browser.