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Discount calculator

Enter a price and a discount — as a percentage or a flat amount — and see what you pay and what you save. Stack a second discount, set a quantity, and the numbers follow as you type.

YOU PAY
$80.00
You save $20.0020% off
Original price
$100.00
Discount
− $20.00

Now find a discount worth calculating

Couponly's free browser extension tries working codes at checkout for you and tells you the moment it finds one that sticks.

How to use the discount calculator

  1. 1

    Enter the original price. The price on the tag, before anything comes off. Change the currency if you need to — it only affects how the result is written.

  2. 2

    Enter the discount. Use the toggle to switch between a percentage (30% off) and a flat amount ($30 off), or tap one of the quick percentages.

  3. 3

    Read what you pay. The result updates as you type, with the amount saved and the effective percentage off. Add an extra discount or a quantity for the full picture.

What common discounts come to

Every figure below is produced by the calculator above, so it matches to the cent.

Sale price and amount saved for common percentage discounts on $25, $50, $100 and $250
Discount$25.00$50.00$100.00$250.00
10% off$22.50save $2.50$45.00save $5.00$90.00save $10.00$225.00save $25.00
15% off$21.25save $3.75$42.50save $7.50$85.00save $15.00$212.50save $37.50
20% off$20.00save $5.00$40.00save $10.00$80.00save $20.00$200.00save $50.00
25% off$18.75save $6.25$37.50save $12.50$75.00save $25.00$187.50save $62.50
30% off$17.50save $7.50$35.00save $15.00$70.00save $30.00$175.00save $75.00
40% off$15.00save $10.00$30.00save $20.00$60.00save $40.00$150.00save $100.00
50% off$12.50save $12.50$25.00save $25.00$50.00save $50.00$125.00save $125.00
60% off$10.00save $15.00$20.00save $30.00$40.00save $60.00$100.00save $150.00
70% off$7.50save $17.50$15.00save $35.00$30.00save $70.00$75.00save $175.00
75% off$6.25save $18.75$12.50save $37.50$25.00save $75.00$62.50save $187.50

Percentage off, amount off, and why stacking isn't addition

A percentage discount scales with the price: 20% off is worth $4 on a $20 shirt and $400 on a $2,000 laptop. A flat amount doesn't — $10 off is $10 whatever you buy, which makes it a bigger effective discount the cheaper the item is. When a store offers you the choice, work out both: $10 off beats 20% off on anything under $50.

Stacked discounts are where the mental arithmetic usually goes wrong. "20% off, plus an extra 10% off sale prices" is not 30% off. The second discount comes off the already-reduced price, so $100.00 becomes $80.00, and 10% off that is $72.00 — 28% off in total. The gap widens as the discounts get bigger: 30% and an extra 30% is 51% off, not 60%.

A coupon code behaves the same way. It normally applies to the subtotal after any sale price, and tax and shipping are calculated afterwards — which is why the number here is your subtotal, not your final total at checkout.

Questions about discounts

How do I calculate a percentage discount?
Multiply the price by the discount percentage, then divide by 100 — that's the amount you save. Subtract it from the price to get what you pay. For 20% off $100.00: 100 × 20 ÷ 100 = $20.00 off, so you pay $80.00.
What is 20% off $100?
$80.00. You save $20.00.
How do stacked discounts work?
A second discount usually comes off the already-reduced price, not the original. So 20% off $100.00 and then an extra 10% off is $72.00 — a total of 28% off, not 30%. Switch on "Add extra discount" above to work this out for any pair.
How do I find the percentage off when I know both prices?
Subtract the sale price from the original price, divide by the original price, then multiply by 100. From $80 down to $60: 20 ÷ 80 × 100 = 25% off.
Does this include sales tax or shipping?
No. It works on the item price alone. Most checkouts apply tax and shipping after the discount, so treat the result as your pre-tax subtotal.
Is the discount calculator free?
Yes — free, no account, and nothing you type is sent anywhere. The whole calculation runs in your browser.
Couponly

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