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Percentage Calculator

Percentage Calculator is a free online tool to calculate percentages.

What is%of?
is what percentof?
What is the percentage increase/decreasefromto?

Tips:

Use tab to move to the next field. Use shift-tab to move to the previous field. Press enter to calculate.

About

This website is designed to help you quickly and easily calculate percentages for a variety of purposes. Whether you're calculating discounts, calculating tips, or trying to figure out how much something has increased or decreased in value, our percentage calculator can help.

FAQ

What is a percentage?

Percentage is a way of expressing a number as a fraction of 100. It is commonly used to represent a portion of a whole or to compare two numbers. Percentages are often denoted with the symbol "%". For example, if there are 100 cars in a garage and 25 of them are white, we could say that 25% of the cars are white.

This percentage calculator solves the three questions people ask most often: what a percentage of a number is, what percentage one number is of another, and how big a percentage change is between two values. Type your numbers into any of the three boxes above and the answer appears instantly — there is nothing to submit and no page reload.

Percentages turn up everywhere: sales tax and tips, exam scores, interest rates, discounts, commission, body-fat readings, opinion polls and year-over-year growth. Because a percentage is just a fraction of 100, every one of those problems reduces to one of the three formulas below.

Percentage formulas

All three calculations above come from the same idea — "per cent" means "per hundred".

  • What is P% of X? result = (P ÷ 100) × X
  • X is what percent of Y? result = (X ÷ Y) × 100
  • Percentage change from A to B? result = ((B − A) ÷ A) × 100
  • Add P% to X? result = X × (1 + P ÷ 100)
  • Subtract P% from X? result = X × (1 − P ÷ 100)

Worked examples

What is 15% of 80?

Multiply 80 by 15, then divide by 100: (15 ÷ 100) × 80 = 0.15 × 80 = 12. A 15% tip on an $80 meal is $12.

37 is what percent of 200?

Divide the part by the whole and multiply by 100: (37 ÷ 200) × 100 = 18.5%. If you scored 37 out of 200 on a test, that is 18.5%.

Percentage increase from 120 to 150

Subtract, divide by the original, multiply by 100: ((150 − 120) ÷ 120) × 100 = (30 ÷ 120) × 100 = 25%. The value rose by 25%.

Percentage decrease from 150 to 120

((120 − 150) ÷ 150) × 100 = (−30 ÷ 150) × 100 = −20%. A drop from 150 to 120 is a 20% decrease — note it is not the same 25% as the increase above.

A price is $63 after a 30% discount — what was the original?

$63 represents 70% of the original price, so original = 63 ÷ 0.70 = $90.

Common uses

  • Working out a tip or splitting a restaurant bill
  • Checking a sale price or how much a discount actually saves you
  • Converting a test score or grade into a percentage
  • Calculating sales tax, VAT or GST on a purchase
  • Measuring month-over-month or year-over-year growth for a business
  • Finding a commission, bonus or markup on a base amount
  • Comparing two figures — for example this year's revenue against last year's

How to use the calculator

  1. Pick the row that matches your question: "what is X% of Y", "X is what percent of Y", or the increase/decrease row.
  2. Type a number into the first field. Use the Tab key to jump to the next field.
  3. Type the second number. The result appears automatically in the highlighted box — there is no calculate button to press.
  4. Change either number at any time to see the answer update live.
  5. For an increase/decrease, enter the original value first ("from") and the new value second ("to"). A negative result means a decrease.

Frequently asked questions

How do I calculate a percentage of a number?

Divide the percentage by 100 and multiply by the number. For 20% of 250: (20 ÷ 100) × 250 = 50.

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

Divide the first number by the second and multiply the result by 100. For 45 out of 60: (45 ÷ 60) × 100 = 75%.

Why isn't a 25% increase cancelled by a 25% decrease?

Each percentage is taken from a different base. 100 increased by 25% is 125; 125 decreased by 25% is 93.75, not 100, because the 25% is now calculated from the larger number.

How do I add or remove a percentage like tax?

To add P%, multiply by (1 + P/100). To remove a percentage that is already included, divide by (1 + P/100). For example, to strip 20% VAT from a $120 gross price: 120 ÷ 1.20 = $100 net.

What is the difference between percentage and percentage points?

A move from 40% to 44% is a rise of 4 percentage points, but a 10% relative increase (4 ÷ 40). News reports often mix the two up.

How do I work out the original amount before a discount?

Divide the final price by (1 − discount/100). A $63 item after 30% off was 63 ÷ 0.70 = $90 before the discount.

Does the calculator round its answers?

Results are shown to two decimal places. The full-precision value is used internally, so chaining calculations stays accurate.

Is my data sent anywhere?

No. Every calculation runs in your browser. Nothing you type is uploaded or stored.

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