Percentage Calculator
About Percentage Calculator
Free online percentage calculator — instantly find what X% of a number is, what percent one number is of another, or percentage change between values.
How to use Percentage Calculator
Use this free percentage calculator to quickly solve common percentage problems: 1. Calculate what a given percentage is of a number (e.g., 20% of 150). 2. Find what percentage one number is of another (e.g., 30 is what % of 200). 3. Calculate the percentage increase or decrease between two values (e.g., change from 100 to 120). Simply enter your numbers and get instant results.
How it works
This tool performs basic percentage arithmetic using standard formulas: Percentage of a number uses (percent / 100) × value. Percentage ratio uses (part / whole) × 100. Percentage change uses ((new - old) / |old|) × 100. All calculations run client-side in your browser for instant results.
Privacy & Security
- ✅ 100% Private: No server-side storage
- ✅ Fast: Zero upload/download latency
- ✅ Secure: Sandbox processing environment