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PercentageCalculator

Calculate percentages, increases, decreases, and changes. Essential for business metrics and analytics.

Basic Percentage

What is X% of Y?

0.00

% of = 0.00

Percentage Increase

Increase X by Y%

0.00

+ % = 0.00

Percentage Decrease

Decrease X by Y%

0.00

- % = 0.00

Percentage Change

What % change from X to Y?

0%

Change: 0% increase

Marketing Metrics

  • • Conversion rate calculations
  • • Growth rate analysis
  • • Campaign performance
  • • ROI measurements

Business Finance

  • • Profit margin calculations
  • • Discount pricing
  • • Tax calculations
  • • Commission rates

Analytics

  • • Website traffic changes
  • • Social media growth
  • • Sales performance
  • • Cost reductions
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What is a Percentage Calculator?

A percentage calculator handles the common percent math people need every day: finding X percent of a number, working out what percent one number is of another, calculating percentage increase or decrease, and converting ratios to percentages. Use it for tip and tax math, sales discounts, markup pricing, grade calculations, marketing growth reports, and any quick check where you want the answer without opening a spreadsheet.

How to use this Percentage Calculator

  1. 1

    Pick the calculation type

    Choose what you need: percent of a number, percent change, what percent X is of Y, or add/subtract a percentage from a value.

  2. 2

    Enter the first value

    Type the base number. For a discount, this is the original price. For growth, the starting value.

  3. 3

    Enter the second value

    Add the percentage or the comparison number. For example, 15 for a 15 percent tip, or the ending value for a percent change calculation.

  4. 4

    Read the result

    The calculator shows the answer and the formula it used so you can verify it or learn the math.

  5. 5

    Switch modes to cross-check

    Use a different mode with the same numbers to double-check, for example confirm a percent increase by computing percent of the new total.

Frequently asked questions

How do I calculate what percent X is of Y?

Divide X by Y, then multiply by 100. So 30 out of 150 is 30 divided by 150 times 100, which equals 20 percent.

How do I work out a percentage increase?

Subtract the old value from the new value, divide by the old value, then multiply by 100. Going from 80 to 100 is a 25 percent increase.

What is 15 percent of 200?

30. To calculate it, multiply 200 by 0.15. The same approach works for any percent of a number: convert the percent to a decimal and multiply.

How do I reverse a percentage to find the original price?

If you know the discounted price and the discount percent, divide the discounted price by (1 minus the discount as a decimal). A $80 item at 20 percent off came from $80 divided by 0.8, or $100.

Why does percent change look different when going down versus up?

Because the base changes. Going from 100 to 80 is a 20 percent decrease, but going from 80 back to 100 is a 25 percent increase. The denominator is the starting value each time.

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