%| Calculate percentage online

7 percentage calculators

Instructions: Write the data in the boxes and press the Calculate button to see the result in the yellow box. In the case of decimals, it is approximated with 2 digits (for example, if the result is 10,998, the calculator provides 11). Calculators write the data in a table and use the rule of three, showing the operations and a percentage bar.

Reminder (theory)

  • A percentage is a particular kind of ratio where the value of the denominator is always equal to 100.

  • \(n\%\) is equal to the fraction \(n/100\), and it means "\(n\) in a hundred".

Examples:

  • 50% is a half of the total number.

  • 25% is a quarter of the total number.

  • 20% is a fifth of the total number.

To calculate a percentage, we will use the rule of three.

Example:

If there are 20 boys in a class of 80 students, the percentage of boys is 15% of the total number of students:

Online percentage calculators: calculate percentage of a number, calculate the total value given a percentage, calculate what percentage of the total is a given number, calculate a percentag given a percentage, calculate the final price after a percentage discount, calculate the final price after a percentage increase and calculate a percentage increase/decrease. Calculators show operations and a percentage bar. The rule of three. Math calculator. Free calculator

85% of the students are girls, since 15% + 85% = 100%.

Calculator 1

Description: calculate the percentage of a number.

% of is .


Operations

\(n\) %
\( x \)
20
200
 100

$$x = \frac{20·200}{100} = 40$$

Representation

↓40
0
200
20%

Calculator 2

Description: calculate the total value given a percentage.

If % is , then the total is .

Operations

\(n\) %
20
10
\(x\) 100

$$x = \frac{20·100}{10} = 200$$

Representation

↓20
0
200
10%

Calculator 3

Description: calculate what percentage of the total is a given number.

If the total is, the is %.

Operations

\(n\) %
40
 \(x\)
200
 100

$$ x = \frac{40·100}{200} = 20\% $$

Representation

↓40
0
200
20%

Calculator 4

Description: calculate a percentage given another percentage.

If % is , then % is .

Operations

\(n\) %
10
60
\(x\)
30

$$ x = \frac{10·30}{60} = 5 $$

Representation

↓5
0
16.67
30%

Calculator 5

Description: calculate the final price after a percentage decrease.

If the original price is $ and we reduce the price by %, the final price will be $.    

Operations

$ %
60
 100
\(x\)
90

$$ x = \frac{60·90}{100} = 54$$
Decrease: $6

Representation

↓54
0
60
90%

Calculator 6

Description: calculate the final price after a percentage increase.

If the original price is $ and we increase the price by %, the final price will be $.   

Operations

$ %
60
 100
\(x\)
110

$$ x = \frac{60·110}{100} = 66$$
Increase: $6

Calculator 7

Description: calculate a percentage increase or decrease knowing the original and final price. A negative percentage indicates a decrease.

If the original price was $, and the final price is $ , then the percentage is %.

Operations

$ %
10
 100
5
 \(x\)

$$ x = \frac{5·100}{10} = 50\%$$
Percentage: -50%
Difference: -5$