Percentage calculator

Five quick percentage calculators in one place. Type in any box and the answer updates instantly.

How to work out percentages

X% of Y: divide X by 100 and multiply by Y. 15% of 80 = 0.15 × 80 = 12.
X as a percentage of Y: divide X by Y and multiply by 100. 30 out of 120 = 30 ÷ 120 × 100 = 25%.
Percentage change: (new − old) ÷ old × 100. From 200 to 250 = 50 ÷ 200 × 100 = 25% increase.
Increase by a percentage: multiply by (1 + rate). 50 increased by 10% = 50 × 1.1 = 55.
Decrease by a percentage: multiply by (1 − rate). 80 reduced by 25% = 80 × 0.75 = 60.

Why does a 50% fall need a 100% rise to recover?

Percentages are measured from the starting value. If £100 falls 50% to £50, it then needs to double (a 100% rise) to get back to £100.

What is the difference between percent and percentage points?

If an interest rate goes from 4% to 5%, it has risen by 1 percentage point, but by 25% in relative terms.