Percentage
Percentage Calculator
Calculate percentages four common ways. Results update instantly as you type.
Mode
%
Result
30
20% of 150 is the answer.
Formula20% × 150 ÷ 100
How it works
A percentage is a fraction of 100. To take a percent of a number, multiply the number by the percent and divide by 100. To express one number as a percent of another, divide the part by the whole and multiply by 100.
Percentage change between two values is the difference divided by the original value, multiplied by 100. A positive result is an increase; a negative result is a decrease.
Frequently asked questions
- How do I calculate a percentage of a number?
- Multiply the number by the percent, then divide by 100. For example, 20% of 150 = 20 × 150 ÷ 100 = 30.
- What is the formula for percentage change?
- Percentage change = (New − Old) ÷ |Old| × 100. A positive number is an increase, a negative number is a decrease.
- Why can't I divide by zero?
- Percentages need a non-zero base. If the original value is 0, percent of and percentage change are mathematically undefined.