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Sale price after discounts
Percent off between two prices
How stacked discounts work
“Extra 20% off sale prices” means 20% off the price that is already reduced, not 20% more off the original. So 30% off and then an extra 20% off is 44% off in total, not 50%:
- $100 with 30% off is $70.
- 20% off $70 is $56.
- $56 is 44% less than $100.
The quick way: multiply what each discount leaves (0.70 × 0.80 = 0.56), and the rest is the real discount (1 − 0.56 = 44%). The calculator shows each step and the total.
Percent off between two prices
When a store shows a “was” and a “now” price, the discount is the difference divided by the old price: from $120 to $89.99 is $30.01 less, or 25% off. If the new price is higher, the calculator shows the rise instead.
Is it really a sale?
A percentage is only as honest as the “was” price it starts from, and that is the price the store chose to show. The surest check is the product’s own price history: if the “sale” price is what it usually costs, the discount isn’t saving you much. The PricePing app records a product’s price from the day you add it and pings you when it drops, at almost any online store. See how to get notified when a price drops.
Questions
How do I calculate a discount?
Multiply the price by (1 − discount ÷ 100). For 30% off $80: 80 × 0.70 = $56, so you save $24. The calculator does this for you and shows the saving.
Is 30% off plus an extra 20% off the same as 50% off?
No. The extra 20% comes off the already-reduced price, so the two together are 44% off: 100 × 0.70 × 0.80 = 56. To combine discounts, multiply what each one leaves (0.70 × 0.80 = 0.56) and subtract from 1.
Does the order of stacked discounts matter?
Not for percentages. 30% then 20% and 20% then 30% both end at 44% off. Order matters only when one of the discounts is a fixed amount, such as $10 off.
How do I work out the percent off between two prices?
Subtract the new price from the old one, divide by the old price and multiply by 100. From $120 to $90: (120 − 90) ÷ 120 × 100 = 25% off.
Is sales tax added before or after the discount?
The calculator adds tax to the discounted price, which is how store discounts usually work in US states with sales tax. Rules for manufacturer coupons vary by state. Prices that already include VAT need no tax added.
Which currency does it use?
Any. Type prices in whatever currency you shop in; the calculator doesn't convert or add a currency symbol.
More free shopping tools
- Amazon link cleaner: Turn a long Amazon product link into the short /dp/ form and strip the tracking. Works for amazon.com, .co.uk, .ae, .sa and other Amazon stores.
- Unit price calculator: Compare packs by price per kg, litre, ounce or item, including multipacks, to see which one is really cheaper.
Want to hear when a price actually drops? See how to get notified when a price drops, or all free tools.
Try PricePing on iPhone. Share a product link from almost any store and get a ping when the price drops. Monthly plans start with a 7-day free trial.
