Percentage Calculator
Solve everyday percentage questions instantly.
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Answer common percentage questions without the mental maths. Work out what X% of a number is, what percentage one number is of another, and the percentage increase or decrease between two values. Results update live as you type, right in your browser.
Three questions that look the same and are not
Most percentage confusion comes from mixing up three separate questions. What is 20 percent of 250 asks for a portion of a known total. 50 is what percent of 250 asks what share one number is of another. And going from 250 to 300 is what percent increase asks about change between two values. They use different arithmetic, which is why doing them in your head so often produces a number that feels wrong.
The increase and decrease trap
A price that rises by 50 percent and then falls by 50 percent does not return to where it started. Take 100, add 50 percent to reach 150, then remove 50 percent of 150 and you land on 75. The second percentage is calculated from the new, larger number. This catches people out constantly with discounts, tax, salary changes and anything reported as a percentage swing.
Everyday uses
- Working out a discount before you reach the till.
- Checking a tax or commission line on an invoice.
- Converting exam marks into a percentage grade.
- Comparing two salary offers where one is quoted as a raise.
How to use Percentage Calculator
- 1
Pick the type of percentage calculation.
- 2
Enter your numbers.
- 3
Read the answer instantly.
Frequently asked questions
Percent of a number, one number as a percent of another, and percentage increase/decrease.