20% Off Calculator

20% off — the go-to promotional discount

Twenty percent off is arguably the most popular promotional discount in e-commerce. It's the default Cyber Monday markdown, the standard coupon tier, and the threshold many shoppers use to decide whether a deal is worth acting on.

At 20% off you pay exactly four-fifths (80%) of the original price. A quick mental shortcut: double the price, drop a zero, that's the saving. For a $75 item — double is $150, drop a zero = $15 saved, sale price $60. Alternatively, simply divide the price by 5 to get the savings directly.

At common price points: $5 off $25, $10 off $50, $20 off $100, $40 off $200. The round numbers are part of why 20% feels so natural — the math produces clean dollar figures.

This discount dominates specific calendar windows. Cyber Monday is the heaviest 20% day of the year for non-apparel categories. Friends-and-family events at department stores typically open at 20% off sitewide.

The most common gotcha is the "20% off list price" framing on items no one actually pays list price for. Mattresses, jewelry, and furniture are notorious — the "MSRP" is set high specifically so a 20% discount brings it down to the standard selling price.

Compared to 25%, the gap is smaller than it looks: on a $100 purchase, it's only a $5 difference. If you're deciding whether to wait for a better promotion, the question is whether the next tier (usually 25% or 30%) historically appears within your purchase window.

How to calculate 20% off

Multiply the original price by 0.80 (which is 1 − 20/100):

Sale Price = Original × 0.80

For example, 20% off $75: $75 × 0.80 = $60.00. You save $15.00.

20% off quick-reference table

Original price	Sale price (20% off)	You save
$10.00	$8.00	$2.00
$20.00	$16.00	$4.00
$25.00	$20.00	$5.00
$50.00	$40.00	$10.00
$75.00	$60.00	$15.00
$100.00	$80.00	$20.00
$150.00	$120.00	$30.00
$200.00	$160.00	$40.00
$250.00	$200.00	$50.00
$500.00	$400.00	$100.00