Reverse Percentage Calculator Online

Percentage

Percent (%)

Number

Result

20% × 150 = 30

Common percentage examples

Type	Calculation	Result
Percent of	20% × 150	30
What percent	30 ÷ 120 × 100	25%
Reverse percent	45 ÷ 0.15	300
Percent change	(100 − 80) ÷ 80 × 100	25%
Convert percent	12.5% ÷ 100	0.125 = 1/8

Work backward from a known percentage value to find the complete amount. Enter the known value and the percentage it represents.

The calculator converts the percentage to a decimal and divides the known value by that decimal. A percentage of zero cannot identify a finite original amount.

Five percentage calculations

Percent of calculates a percentage of a given number.
What percent finds what percentage one value represents of another.
Reverse percent finds the whole when a value and its percentage are known.
Percent change compares a new value with its original value.
Convert percent returns the equivalent decimal and simplified fraction.

Percentage change uses the absolute original value as the denominator, so direction remains meaningful when values are negative. A positive result is an increase and a negative result is a decrease. Change from an original value of zero is undefined because division by zero has no finite percentage result.

Related percentage calculations: Grade Calculator · Percentage Calculator · Percentage Change · Reverse Percentage · Percent to Decimal