Online Percentage Calculator
Three modes - percentage of, what percent, and percent change - real-time calculation, fully client-side
FAQ
Three common calculations: X% of Y, X as a percentage of Y, and the value after increasing or decreasing X by Y%.
Decimals and negatives are supported, as well as thousands separators (1,234) and percent suffixes (15%). For example, to get 15% of 200, simply enter 200 and 15.
Dividing by zero is mathematically undefined, so the tool shows 'The total cannot be zero'. Check your input.
No. All calculations happen locally in your browser. Your data never leaves your device.
Up to 6 decimal places, with trailing zeros automatically trimmed - enough precision for most use cases.
Completely free. This is a pure frontend online tool - no registration required, no payment needed, just open and use.
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