Percentage Calculator
Calculate a percentage of a number, find what percent one number is of another, measure percentage change, or increase and decrease values by a percentage. Free and instant — the calculation runs in your browser with no sign-up.
How to calculate a percentage
This calculator covers the four most common percentage tasks. Pick a mode, enter your real numbers, and the result is computed instantly in your browser. Calculations that would divide by zero are undefined and are reported clearly rather than shown as an error value.
The formulas
- Percentage of a number: (number × percentage) ÷ 100
- What percent one number is of another: (part ÷ whole) × 100
- Percentage change: ((new value − original value) ÷ original value) × 100
- Increase a value by a percentage: value × (1 + percentage ÷ 100)
- Decrease a value by a percentage: value × (1 − percentage ÷ 100)
- Dividing by zero (a whole or original value of 0) is undefined.