Percentage Calculator (What % of, % of a number, reverse)
Three basic percentage calculations in one: what percent A is of B, a given percent of a number, and the whole from a part and its percentage. Enter two numbers to instantly get the percent or amount, with your choice of decimal places and rounding.
Input
Calculation type
Rounding
Round half up
Result
A as a percent of B
15%
30 is 15% of 200.
How it works
- 'What percent is A of B?' divides the compared value A by the base value B and multiplies by 100 (percent = A ÷ B × 100). Example: 30 is 15% of 200.
- 'What is X% of a number?' multiplies the base by the percentage and divides by 100 (amount = base × percent ÷ 100). Example: 15% of 800 is 120.
- 'A is X% of what?' divides the part by the percentage and multiplies by 100 to recover the whole (whole = part ÷ percent × 100). Example: if 120 is 15%, the whole is 800.
- A base value or percentage of 0 cannot be computed (it would divide by zero); check your inputs in that case.
- Results are shown rounded to the number of decimal places you choose, using the selected rounding mode (round half up, round down, or round up).
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Percentage Calculator (What % of, % of a number, reverse)