Skip to content

Percentage calculator

X% of a number, what percent one number is of another, and the percent change between two numbers.

Favorite

Results

Answer 30

How it works

part = whole × % ÷ 100

“Percent” means “per hundred”, so 15% is 15 ÷ 100 = 0.15. All three questions use that one idea: multiply by the percent and divide by 100 to get a part; divide the part by the whole and multiply by 100 to get the percent; and for a change, divide the difference by the starting value. A change is measured from where you started, so going from 80 to 100 is +25%, but 100 back to 80 is −20%.

  1. Multiply by the percent, divide by 100 200 × 15 ÷ 100 = 30

Printed from rocketcalc.io/math/percentage