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Percentage Calculator

Solve percent of a number, what percent one number is of another, percentage change, increases, decreases, fractions, and percentage points.

Result

31.25

Mode

Percent of number

Formula

number x percent / 100

Percentage inputs

Calculate percentages

Result details

Answer
31.25
Rounded number
31.25
Formula
number x percent / 100
Unit
number

Calculation

12.5% of 25031.25
Step250 x 12.5 / 100

Result actions

Percentage formulas and examples

Use the calculator for percent-of, percent-change, percentage increase, percentage decrease, fractions, and percentage-point comparisons.

Percent of a number

To find X percent of Y, multiply Y by X and divide by 100. Example: 15% of 80 is 80 x 15 / 100, which equals 12.

What percent one value is

To find what percent X is of Y, divide X by Y and multiply by 100. Example: 18 is 30% of 60 because 18 / 60 x 100 equals 30%.

Percent change

Percent change compares a new value to an old value. Moving from 40 to 50 is a 25% increase because the difference is 10 and 10 / 40 x 100 equals 25%.

Common uses

  • Calculate sale discounts and coupon savings.
  • Compare rate changes, growth, loss, and performance.
  • Convert fractions or ratios into percentages.
  • Separate percentage-point changes from relative percent changes.

Percentage calculators by formula

Start on a focused percentage page when the question is about one specific formula or comparison.

Percentage calculator formulas

Percent of a number uses number x percent / 100. Percent change uses (new value - old value) / absolute old value x 100, which keeps the direction clear even when the starting number is negative.

Percentage points are different from percent change. Moving from 4% to 5% is a 1 percentage point increase, but a 25% relative increase.

Frequently asked questions

What percentage calculations are supported?

The calculator covers percent of a number, what percent one number is of another, percent change, percentage increase, percentage decrease, fractions, and percentage-point differences.

What is the formula for X percent of Y?

X percent of Y equals Y multiplied by X divided by 100. For example, 15% of 80 is 80 x 15 / 100, which equals 12.

What is the difference between percent and percentage points?

Percent change is relative to the starting value. Percentage points measure the direct difference between two percentages, such as moving from 4% to 5%.

Can this calculator handle decreases and negative changes?

Yes. Percent change uses the difference between the new and old values divided by the absolute old value so increases, decreases, and negative starting values are easier to interpret.

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