Free Percentage Calculator — All Percentage Operations
Percentage calculations appear in almost every aspect of daily life and business: discounts while shopping, tax rates, investment returns, grade calculations, tips at restaurants, pay rises, and much more. Our free percentage calculator handles five of the most common percentage operations with a clean, intuitive interface.
Whether you need to find what percentage one number is of another, calculate an increase or decrease, or find the percentage change between two values — select the operation type, enter your numbers, and get the result instantly.
5 Calculation Modes
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X% of Y
Find the value of a percentage. "What is 15% of 200?"
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X is what % of Y?
"80 is what percentage of 400?" → 20%
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Increase by %
Apply a percentage increase to any base value.
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Decrease by %
Calculate sale prices, discounts, reductions.
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% Change
Find the percentage increase or decrease between two values.
Frequently Asked Questions
How do I calculate what percentage one number is of another?▼
Divide the first number by the second and multiply by 100. Example: 80 is what % of 400? → 80/400 × 100 = 20%. Select 'What % is X of Y?' in our calculator for instant results.
How do I calculate a percentage increase?▼
Divide the increase by the original value and multiply by 100. Example: price went from 80 to 100 → increase = 20 → 20/80 × 100 = 25% increase. Use our 'Percentage change' mode.
What is 15% of 200?▼
15% of 200 = (15/100) × 200 = 30. Use our 'X% of Y' mode and enter 15 and 200 to confirm instantly.
How do I calculate a discount price?▼
If a product costs €150 and has a 20% discount: discounted price = 150 × (1 - 20/100) = 150 × 0.8 = €120. Use 'Decrease by %' mode in our calculator.
Can I calculate percentage change between two values?▼
Yes. Enter the starting and ending values in 'Percentage change' mode. The tool will calculate the percentage increase or decrease, including negative changes (percentage decrease).