// Free Online Tool
Percentage Calculator
Four calculation modes. Instant results. No page reload, no signup.
What is X% of Y?
Frequently Asked Questions
Divide the percentage by 100, then multiply by the number.
Formula: (X ÷ 100) × Y
Example: What is 20% of 150? → (20 ÷ 100) × 150 = 30
Divide the part (X) by the whole (Y) and multiply by 100.
Formula: (X ÷ Y) × 100
Example: 50 is what % of 200? → (50 ÷ 200) × 100 = 25%
Multiply the original value by (1 + percentage ÷ 100).
Formula: Y × (1 + X ÷ 100)
Example: Increase 200 by 15% → 200 × 1.15 = 230
Multiply the original value by (1 − percentage ÷ 100).
Formula: Y × (1 − X ÷ 100)
Example: Decrease 500 by 20% → 500 × 0.80 = 400
Mental math with percentages is error-prone, especially with decimals or large numbers. An online calculator gives you instant, accurate results across all four common percentage operations — no pen, paper, or Google Sheets required.
About This Percentage Calculator
This tool handles all everyday percentage math in one place. Whether you're splitting a restaurant bill, figuring out a sale discount, calculating a tax amount, or analysing data — the four modes cover everything:
- % of Number — find a fraction of any value (e.g. tips, taxes, discounts)
- X is what %? — express one number as a proportion of another (e.g. test scores, conversion rates)
- Increase by % — apply a percentage markup (e.g. price hikes, salary raises)
- Decrease by % — apply a percentage discount (e.g. sale prices, budget cuts)
Results update in real-time as you type and can be copied to clipboard with one click.
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