How do I take a percentage off a number?

Multiply by 1 minus the percentage as a decimal. 250 less 12% is 250 x 0.88 = 220. This is the same arithmetic a discount uses.

Can something decrease by more than 100%?

Not if it cannot go below zero, which is the case for a price or a quantity. A decrease of 100% leaves nothing. Figures like profit can fall by more than 100% because they can turn negative, which is why a percentage fall in profit is often a misleading way to describe a loss.

Math & Statisticspercentage

Percentage Decrease Calculator

Decrease a number by a percentage, with the amount removed shown separately.

Also called: percent decrease calculator, how much did it fall.

After the decrease

880

1,000 decreased by 12% is 880, a decrease of 120.

Amount of the decrease

120

How this is calculated

Method and background

How this is calculated

Multiply by one minus the percentage. A 100% decrease reaches zero and anything beyond it goes negative, which the tool will show rather than clamp.

result = value * (1 - percent/100)

p: The decrease, in percent

Worked examples

Each of these is asserted on every build. If a change to the engine ever moved one of these answers, the build would fail before the page could print it.

1000 down 12%

Starting value: 1,000
Decrease by (%): 12

After the decrease880

arithmetic identity

Open this example

a 100% decrease reaches zero

Starting value: 1,000
Decrease by (%): 100

After the decrease0

boundary

Open this example

zero decrease

Starting value: 1,000
Decrease by (%): 0

After the decrease1,000

degenerate case

Open this example

Frequently asked questions

How do I take a percentage off a number?: Multiply by 1 minus the percentage as a decimal. 250 less 12% is 250 x 0.88 = 220. This is the same arithmetic a discount uses.
Can something decrease by more than 100%?: Not if it cannot go below zero, which is the case for a price or a quantity. A decrease of 100% leaves nothing. Figures like profit can fall by more than 100% because they can turn negative, which is why a percentage fall in profit is often a misleading way to describe a loss.