To take a percentage off a price, multiply the price by (1 − percent ÷ 100). 40% off $60 is $60 × 0.60 = $36, saving $24. 30% off $40 is $28, and 20% off $100 is $80. Two discounts in a row multiply, so 20% off then 10% off is 28% off, not 30%.
The calculator gives the sale price and your savings, stacks an extra discount, adds sales tax, and works backwards from a sale price to the original price. All you need is the tag price and the discount.
How to use this calculator
- Enter the original price and the percent off.
- For an "extra 10% off sale prices" deal, put the second discount in "Extra % off".
- Add your sales tax rate to see what you pay at the register.
- Switch to "Original price from sale price" to find what an item cost before the discount.
Percent off formula
- Sale price = price × (1 − % ÷ 100)
- You save = price × % ÷ 100
- Stacked discounts = price × (1 − a ÷ 100) × (1 − b ÷ 100)
- Original price = sale price ÷ (1 − % ÷ 100)
- With tax = sale price × (1 + tax rate ÷ 100)
A quick mental shortcut: 10% off moves the decimal one place (10% of $38 is $3.80), so 20% is double that and 30% is triple. 50% off is half, and 25% off is a quarter less.
Percent off chart
Sale prices for common prices from $10 to $500 at 10% to 75% off, before tax and rounded to the cent. Find your price in the left column and the discount along the top; for other prices, use the calculator.
| Price | 10% off | 15% off | 20% off | 25% off | 30% off | 35% off | 40% off | 50% off | 60% off | 70% off | 75% off |
|---|---|---|---|---|---|---|---|---|---|---|---|
| $10 | $9 | $8.50 | $8 | $7.50 | $7 | $6.50 | $6 | $5 | $4 | $3 | $2.50 |
| $15 | $13.50 | $12.75 | $12 | $11.25 | $10.50 | $9.75 | $9 | $7.50 | $6 | $4.50 | $3.75 |
| $20 | $18 | $17 | $16 | $15 | $14 | $13 | $12 | $10 | $8 | $6 | $5 |
| $25 | $22.50 | $21.25 | $20 | $18.75 | $17.50 | $16.25 | $15 | $12.50 | $10 | $7.50 | $6.25 |
| $30 | $27 | $25.50 | $24 | $22.50 | $21 | $19.50 | $18 | $15 | $12 | $9 | $7.50 |
| $35 | $31.50 | $29.75 | $28 | $26.25 | $24.50 | $22.75 | $21 | $17.50 | $14 | $10.50 | $8.75 |
| $40 | $36 | $34 | $32 | $30 | $28 | $26 | $24 | $20 | $16 | $12 | $10 |
| $45 | $40.50 | $38.25 | $36 | $33.75 | $31.50 | $29.25 | $27 | $22.50 | $18 | $13.50 | $11.25 |
| $50 | $45 | $42.50 | $40 | $37.50 | $35 | $32.50 | $30 | $25 | $20 | $15 | $12.50 |
| $60 | $54 | $51 | $48 | $45 | $42 | $39 | $36 | $30 | $24 | $18 | $15 |
| $70 | $63 | $59.50 | $56 | $52.50 | $49 | $45.50 | $42 | $35 | $28 | $21 | $17.50 |
| $75 | $67.50 | $63.75 | $60 | $56.25 | $52.50 | $48.75 | $45 | $37.50 | $30 | $22.50 | $18.75 |
| $80 | $72 | $68 | $64 | $60 | $56 | $52 | $48 | $40 | $32 | $24 | $20 |
| $90 | $81 | $76.50 | $72 | $67.50 | $63 | $58.50 | $54 | $45 | $36 | $27 | $22.50 |
| $100 | $90 | $85 | $80 | $75 | $70 | $65 | $60 | $50 | $40 | $30 | $25 |
| $120 | $108 | $102 | $96 | $90 | $84 | $78 | $72 | $60 | $48 | $36 | $30 |
| $125 | $112.50 | $106.25 | $100 | $93.75 | $87.50 | $81.25 | $75 | $62.50 | $50 | $37.50 | $31.25 |
| $150 | $135 | $127.50 | $120 | $112.50 | $105 | $97.50 | $90 | $75 | $60 | $45 | $37.50 |
| $175 | $157.50 | $148.75 | $140 | $131.25 | $122.50 | $113.75 | $105 | $87.50 | $70 | $52.50 | $43.75 |
| $200 | $180 | $170 | $160 | $150 | $140 | $130 | $120 | $100 | $80 | $60 | $50 |
| $250 | $225 | $212.50 | $200 | $187.50 | $175 | $162.50 | $150 | $125 | $100 | $75 | $62.50 |
| $300 | $270 | $255 | $240 | $225 | $210 | $195 | $180 | $150 | $120 | $90 | $75 |
| $400 | $360 | $340 | $320 | $300 | $280 | $260 | $240 | $200 | $160 | $120 | $100 |
| $500 | $450 | $425 | $400 | $375 | $350 | $325 | $300 | $250 | $200 | $150 | $125 |
Stacked discounts: why 20% + 10% isn't 30%
"Take an extra 10% off sale prices" means 10% off the already-reduced price. The combined discount is always less than the sum. The table shows the total discount and what a $100 item ends up costing.
| First discount | Then | Total discount | $100 item costs |
|---|---|---|---|
| 20% | 10% | 28% | $72 |
| 20% | 20% | 36% | $64 |
| 25% | 10% | 32.5% | $67.50 |
| 30% | 10% | 37% | $63 |
| 30% | 20% | 44% | $56 |
| 40% | 10% | 46% | $54 |
| 40% | 20% | 52% | $48 |
| 50% | 10% | 55% | $45 |
| 50% | 20% | 60% | $40 |
| 50% | 50% | 75% | $25 |
Order doesn't matter for two percentage discounts: 10% then 20% gives the same $72. It does matter when one is a dollar amount: $10 off then 20% off $100 is $72, while 20% off then $10 off is $70.
Original price from sale price
What an item cost before the discount, given what you paid (sale price ÷ (1 − discount)).
| You paid | after 20% off, was | after 25% off, was | after 30% off, was | after 40% off, was | after 50% off, was |
|---|---|---|---|---|---|
| $10 | $12.50 | $13.33 | $14.29 | $16.67 | $20 |
| $20 | $25 | $26.67 | $28.57 | $33.33 | $40 |
| $25 | $31.25 | $33.33 | $35.71 | $41.67 | $50 |
| $30 | $37.50 | $40 | $42.86 | $50 | $60 |
| $36 | $45 | $48 | $51.43 | $60 | $72 |
| $50 | $62.50 | $66.67 | $71.43 | $83.33 | $100 |
| $75 | $93.75 | $100 | $107.14 | $125 | $150 |
| $100 | $125 | $133.33 | $142.86 | $166.67 | $200 |
Don't add the percent back on: $36 plus 40% is $50.40, not the original $60.
Sales tax on discounted items
The calculator adds tax to the sale price. That matches how New York treats a store's own discount: its tax department says that because the seller isn't reimbursed for a store coupon, "tax is calculated on the reduced price." A manufacturer's coupon is different: New York says sales tax is due on the full price, because the manufacturer pays the store back. California's CDTFA Publication 113 draws the same line between discounts the retailer absorbs and ones a third party reimburses. For example, $60 at 40% off with 8% tax is $36 + $2.88 tax = $38.88. Rates and rules vary by state and city, so enter your local rate.
Is the "original price" real?
A percent off is only as honest as the price it starts from. The FTC's Guides Against Deceptive Pricing say a former-price comparison is legitimate when the former price is "the actual, bona fide price at which the article was offered to the public on a regular basis for a reasonably substantial period of time" (16 CFR § 233.1(a)). A price inflated just so it can be "cut" makes the bargain false. The guides also warn that a tiny cut, such as "reduced to $9.99" from $10, misleads shoppers who expect a real saving (§ 233.1(e)). Comparing prices at other stores before you buy is the best check.
Common mistakes
- Adding stacked discounts. 50% off plus 50% off is 75% off, not free.
- Reversing a discount by adding the percent back. Divide by (1 − %) instead.
- Confusing "40 off" with $40 off. In a sale, "40 off" nearly always means 40 percent. $40 off $60 would be $20.
- Forgetting tax. Add your local sales tax rate to see what you'll actually pay.
The same percentage maths works elsewhere: the pay raise calculator applies it to a salary, and the grade calculator turns test scores into percentages.
Frequently asked questions
How do you calculate percent off?
Multiply the price by (1 − percent ÷ 100). For 40% off $60: $60 × 0.60 = $36. The savings are price × percent ÷ 100: $60 × 0.40 = $24. Working with the percentage you keep (60%) is one step instead of two, and avoids subtracting the wrong number.
How do I work out what percent off I got?
Divide the sale price by the original price, subtract from 1 and multiply by 100. Paying $36 for a $60 item is (1 − 36 ÷ 60) × 100 = 40% off. Useful when a tag shows only "was" and "now" prices.
Is buy one, get one 50% off the same as 25% off?
On two items of the same price, yes: you pay 1.5 prices for 2 items, which is 25% off each. Two $40 items cost $40 + $20 = $60, the same as 25% off $80. If the prices differ, the half-off usually applies to the cheaper item, so the overall saving is less than 25%.
Is 20% off and then 10% off the same as 30% off?
No. The second discount applies to the already-reduced price: $100 × 0.80 × 0.90 = $72, which is 28% off in total, not 30%. On $100 that's $2 more than a straight 30% off.
How do I find the original price from the sale price?
Divide the sale price by (1 − percent ÷ 100). If you paid $36 after 40% off, the original price was $36 ÷ 0.60 = $60.
Is sales tax charged on the sale price or the original price?
For a store's own discount, on the reduced price in states such as New York: its tax department says tax is calculated on the reduced price because the seller isn't reimbursed. With a manufacturer's coupon, New York taxes the full price, because the manufacturer reimburses the store. Rules vary by state.
Sources & method
- FTC Guides Against Deceptive Pricing, 16 CFR Part 233 (eCFR) — former-price comparisons, § 233.1
- New York State Dept. of Taxation and Finance — Coupons (tax on store-discounted vs manufacturer-coupon prices)
- California CDTFA Publication 113 — Coupons, Discounts, and Rebates
Results are estimates for general information. Found an error? It helps everyone — see our methodology.