Calculators
Percentage Calculator
Solve everyday percentage problems: what is X% of Y, X is what percent of Y, and percent increase/decrease. Instant results with clear formulas — no spreadsheet required.
Runs entirely in your browser. Your data never leaves this device.
- % of a number
- X is what % of Y
- Increase / decrease
- Clear formulas
- Copy results
Workspace
Client-side · No upload
How it works
- Pick a calculation mode.
- Enter the two numbers.
- Read the result and formula.
Key features
- % of a number
- X is what % of Y
- Increase / decrease
- Clear formulas
- Copy results
FAQ
Rounding?
Results show sensible decimal places for money-like use.
Negative change?
Percent decrease is supported.
Private?
Yes.
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