Calculators

Percentage Calculator

Calculate a percentage of a number, find what percent one value is of another, or measure percentage increase and decrease. Results update instantly with no signup required.

successful runs
upvotes
comments
%

Your numbers stay on your device. Percentage calculations run in your browser, and no account or financial information is required.

How to Use the Percentage Calculator

  1. Choose the percentage question you want to answer.
  2. Enter the two requested values.
  3. Read the result and the equation shown beneath it.
  4. Use Reset to clear the values and start another calculation.

How Percentage Calculations Work

To find X percent of Y, divide X by 100 and multiply by Y. To find what percent X is of Y, divide X by Y and multiply by 100. Percentage change compares the difference between the new and original values with the original value: (new − original) ÷ |original| × 100.

A positive percentage change is an increase and a negative result is a decrease. Percentage change cannot use zero as the original value because division by zero is undefined.

Percentage Calculator Examples

What is 20% of 150?

Convert 20% to 0.20, then multiply 150 × 0.20. The result is 30.

What percentage is 25 of 200?

Divide 25 by 200 and multiply by 100. The result is 12.5%.

What is the percentage increase from 80 to 100?

The increase is 20. Divide 20 by the original value of 80 and multiply by 100. The percentage increase is 25%.

Percentages Above 100% and Negative Percentages

A percentage can be greater than 100% when a part is larger than the reference amount. For example, 150 is 150% of 100. Negative percentages can describe values below zero or decreases, but the meaning depends on the quantities being compared.

Community discussion

Comments

Share feedback about the tool. Don’t include private calculation inputs or account details.

0
Loading discussion…

Method, sources, and review

Built and maintained by
TheToolSite AutomationAutomation
Method reviewed by
Derrick Frye
Last reviewed
August 19, 2026
Publisher
TheToolSite

Methodology

Multiplies the entered amount by the entered percentage and divides by 100.

Assumptions

Limitations

This is arithmetic only and does not determine taxes, rates, eligibility, or professional advice.

Rounding and precision

The interface displays the result to two decimal places; calculations use JavaScript number precision.

No external factual standard or dataset is used for this tool.

Report a problem with this result or source

Percentage Calculator FAQ

How do I calculate a percentage of a number?

Divide the percentage by 100, then multiply by the number. For example, 15% of 80 is 0.15 × 80, which equals 12.

How do I calculate percentage increase or decrease?

Subtract the original value from the new value, divide that difference by the absolute original value, and multiply by 100. A positive result is an increase; a negative result is a decrease.

How do I find what percentage one number is of another?

Divide the first number by the second number and multiply by 100. The second number cannot be zero.

Can a percentage be greater than 100%?

Yes. Percentages above 100% mean the measured amount is greater than the reference amount. For example, 250 is 125% of 200.

Learn More About Percentage