Percentage Calculator
What is % of ?
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is what % of ?
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From to
Percentage Change
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increased by %
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A versatile percentage calculator with four modes covering the most common percentage problems: finding X% of a number, determining what percentage one number is of another, calculating percentage change between two values, and applying a percentage increase or decrease. Perfect for quick calculations on discounts, profit margins, tips, and more.
Why Use This Percentage Calculator?
- Four modes — handles every common percentage scenario in one tool.
- Live results — answers update instantly as you type, no button clicks needed.
- Precise output — results show up to 4 decimal places, trailing zeros removed automatically.
- Works offline — runs entirely in your browser with zero server calls.
Key Features
- X% of Y: Calculate any percentage of any number (e.g., 15% of 250).
- X is ?% of Y: Find the percentage ratio between two numbers.
- % Change: Compute the percentage increase or decrease from one value to another.
- X ± Y%: Apply a percentage increase (or decrease with negative values) to a number.
How it Works
Each mode applies a simple arithmetic formula: “X% of Y” = (X/100) × Y, “X is ?% of Y” = (X/Y) × 100, “% Change” = ((New − Old) / |Old|) × 100, and “X + Y%” = X × (1 + Y/100). Results are calculated on every keystroke for instant feedback.
Try the Percentage Calculator
Switch between the four tabs above and enter your numbers. The result updates live — no need to press any button.