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Calculate percentages instantly

Answer the three everyday percentage questions: what is 15% of 80, 12 is what percent of 80, and 12 is 15% of what. Results appear as you type.

Calculations run on this device. We don't see, store or log the numbers or dates you enter.

How it works

  1. Pick the question that matches yours.
  2. Type the two numbers you know.
  3. Read the answer below the fields, or tap Copy.

The three percentage formulas

Percent of a number: 15% of 80 = 0.15 × 80 = 12. What percent: 12 ÷ 80 × 100 = 15%. The whole from a part: 12 ÷ 0.15 = 80. Every percentage problem is one of these three, only the unknown changes.

Everyday examples

A 20% tip on a bill of 45 is 9. If 18 of 24 students passed, 18 ÷ 24 × 100 = 75% passed. If 6% sales tax came to 4.20, the price before tax was 4.20 ÷ 0.06 = 70.

Tips for accurate results

Enter numbers with a dot or a comma as the decimal separator, whichever you normally use. Results are shown with up to 4 decimals; for a change between two values, such as a price rise, use the percentage change calculator instead.

Frequently asked questions

How do I calculate a percentage of a number?

Multiply the number by the percentage divided by 100. For example, 30% of 250 = 0.30 × 250 = 75.

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

Divide the part by the whole and multiply by 100. For example, 45 of 60 = 45 ÷ 60 × 100 = 75%.

Can percentages be over 100?

Yes. 150 is 150% of 100, and 200% of 30 is 60.

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