MultiConvers

Percentage Calculator

Answer the three everyday percentage questions: what is X% of Y, what percent is X of Y, and what total has X as Y% of it — not a percent-change between two totals.

How to use

  1. Choose the mode that matches the sentence you would say out loud.
  2. Enter the two numbers. The percentage field is “20” for 20%, not 0.20.
  3. Read the result. Switch mode instead of rearranging the same numbers by hand.
  4. Use Percentage Change when you have an old value and a new value, not a part and a whole.

How it works

A percentage is a part compared with a whole, scaled so the whole is 100. The same idea shows up as a shop discount, a test score, a tax, or a tip. The arithmetic changes with the question, which is why this page has three modes instead of one box.

“What is 20% of 50?” is the first mode: divide 20 by 100 and multiply by 50 to get 10. That is a discount of 20% off a 50 price only if 20% is the discount rate — the remaining price would be 40, which is a different sentence (100% − 20%). This calculator returns the percentage amount, not the leftover, unless you ask the leftover as its own problem.

“10 is what percent of 50?” is the second mode: 10 ÷ 50 × 100 = 20%. Use this for scores (18 of 25), turnout, or “what share of the budget is this line”. If the total is zero the percentage is undefined; the calculator will not invent a number.

“10 is 20% of what?” is the third mode: 10 ÷ 0.20 = 50. Use it when you know a tax amount and the rate, or a tip and the tip percent, and you want the original bill. People often swap this with percent-of and get 2 instead of 50.

Percent increase from 50 to 60 is not any of these three. That is (60 − 50) ÷ 50 × 100 = 20% change, on the Percentage Change page. Discount and markup tools exist when the story is a price going down or a cost going up to a selling price.

Formula

X% of Y = (X ÷ 100) × Y
X is what % of Y = (X ÷ Y) × 100
X is Y% of what = X ÷ (Y ÷ 100)

Worked examples

  • What is 20% of 50?

    20% of 50 → 10

  • 10 is what percent of 50?

    10 is what % of 50 → 20%

  • 10 is 20% of what number?

    10 is 20% of what → 50

Useful notes

  • Enter 20 for 20%, not 0.20. The calculator divides by 100.
  • Percent change between two totals is a different page.
  • A zero total in “what percent of” cannot be computed.

FAQ

How do I calculate a percentage of a number?

Divide the percentage by 100 and multiply by the number. For example, 20% of 50 is (20 ÷ 100) × 50 = 10.

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

Divide the part by the whole and multiply by 100. For example, 10 is (10 ÷ 50) × 100 = 20% of 50.

How do I find the total when I know a part and a percentage?

Divide the part by the percentage expressed as a decimal. For example, if 10 is 20% of a number, the number is 10 ÷ 0.20 = 50.

Is 20% off the same as 20% of?

20% of 50 is 10. 20% off 50 is 50 − 10 = 40. This page computes the 10 unless you run a second subtraction.

Where do I calculate a raise from 40,000 to 44,000?

That is percentage change: (44,000 − 40,000) ÷ 40,000 × 100 = 10%. Use the Percentage Change tool.

Guides

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