Calculate sale price, savings amount, and discount percentages for any purchase
Calculating discounts is a fundamental skill for both shoppers and retailers. Whether you're trying to figure out how much you'll save during a sale or setting promotional pricing for your business, understanding discount math is essential.
The basic discount formula is simple: multiply the original price by the discount percentage (as a decimal), then subtract from the original price. For a $80 item at 25% off: $80 × 0.25 = $20 savings, so you pay $60.
This calculator handles three scenarios: finding the sale price from an original price and discount, calculating what discount percentage was applied, and working backwards to find the original price before a discount.
The most common type. '30% off' means you pay 70% of the original price.
'$20 off' or 'Save $50'. Convert to percentage by dividing by original price.
BOGO 50% off = 25% off total. BOGO free = 50% off when buying 2 items.
Tiered pricing that rewards larger purchases. Calculate per-unit savings.
When multiple discounts apply, the order matters and they don't simply add up. Two 20% discounts don't equal 40% off—they result in 36% total savings.
Here's why: Start with $100. First 20% off: $100 × 0.80 = $80. Second 20% off: $80 × 0.80 = $64. Total savings: $36 (36%), not $40.
| First Discount | Second Discount | Total Savings | Final Price |
|---|---|---|---|
| 10% | 10% | 19% | $81.00 |
| 20% | 10% | 28% | $72.00 |
| 20% | 20% | 36% | $64.00 |
| 25% | 25% | 43.75% | $56.25 |
| 30% | 20% | 44% | $56.00 |
| 40% | 20% | 52% | $48.00 |
| 50% | 20% | 60% | $40.00 |
| 50% | 50% | 75% | $25.00 |
Don't rely on 'SAVE $50' signs. Calculate the actual percentage to see if it's really a good deal.
A 'sale' on a larger size isn't always cheaper. Calculate price per unit to find true savings.
Some items get 'discounted' from inflated prices. Use price tracking tools to verify actual savings.
Combine store sales with coupons, credit card rewards, and cashback apps for maximum savings.
A shopper sees a $100 jacket marked 25% off and wants to confirm the sticker math before checking out.
ResultSavings $25.00, sale price $75.00, badge reads 25.0% OFF.
The calculator runs Sale Price = 100 × (1 − 25/100) = 100 × 0.75 = $75. Savings is the difference: $100 − $75 = $25. Most U.S. states then apply sales tax to the $75 discounted price, not the $100 original — so the final at-register total at a 7% rate would be $75 × 1.07 = $80.25.
A retailer is running 30% off the rack, and the buyer also has an extra 10% off coupon on top. They want to know the true total savings on a $200 item.
ResultFirst markdown: $200 × 0.70 = $140. Coupon applied to the marked-down price: $140 × 0.90 = $126. Total savings $74 (37% effective), not 40%.
Stacked discounts multiply, not add. The effective discount is 1 − (1 − 0.30)(1 − 0.10) = 1 − 0.63 = 0.37, or 37%. To reproduce this in the calculator, run Find Sale Price with 200 and 30 to get $140, then run it again with 140 and 10 to get $126. If you instead applied 40% off in a single pass, the sale price would be $120 — $6 less than the real stacked result.
A used-camera listing dropped from $480 to $336. The buyer wants to know what percentage off that represents and whether the seller's claim of '30% off' is accurate.
ResultSavings $144.00, discount 30.0%, sale price $336.00.
Switch to Find Discount % mode so the Original Price and Sale Price fields are visible. The formula is Discount % = (Original − Sale) / Original × 100 = (480 − 336) / 480 × 100 = 144 / 480 × 100 = 30%. The seller's claim checks out exactly. If the numbers had been $480 and $340, the discount would be 29.2%, not 30% — useful when ad copy rounds aggressively.
Sale price uses the standard markdown formula . A $100 item at 25% off becomes 100 × 0.75 = $75, with $25 in savings. Multiplying by (1 − rate) once is equivalent to subtracting the rate × original price, but it composes more cleanly when you stack discounts.
Find Discount % mode inverts the relationship: given an original price and a sale price, it computes . This is the same metric retailers print on price tags and is the unambiguous way to compare two different markdowns.
Find Original Price mode solves for the pre-sale price when you only know the sale price and the discount: . For example, $60 after 25% off implies an original of 60 / 0.75 = $80. The calculator caps discount at 99.99% internally to avoid division by zero.
Stacked discounts are multiplicative, not additive. Two sequential discounts of and produce an effective discount of . That's why 30% + 10% saves 37%, not 40% — the second discount is taken on an already-smaller base, so it removes fewer dollars than the first.
Multiply the original price by the discount as a decimal to get the savings, then subtract from the original price. The shortcut: multiply the original by (1 − discount/100) for the sale price in one step. Example: $80 at 25% off is 80 × 0.75 = $60.
Multiply the price by 0.20 to find the discount amount, then subtract from the original. Or simply multiply by 0.80 to get the sale price directly. Example: $50 × 0.80 = $40 sale price.
Because each discount applies to whatever price remains after the previous one. A 30% discount removes $30 from a $100 item, leaving $70. A second 10% discount then removes 10% of $70 — only $7 — for a total of $37 off, or 37%. The effective stacked rate is 1 − (1 − d₁)(1 − d₂), not d₁ + d₂.
In most U.S. states, sales tax is charged on the post-discount price for ordinary store coupons and price reductions. A few states (and most manufacturer coupon scenarios where the store is reimbursed) tax the pre-discount price. Check your state's department of revenue rules if you need precision.
Divide the sale price by (1 − discount/100). If something is $60 after 25% off, that's 60 ÷ 0.75 = $80 original. The Find Original Price mode in this calculator does the same math automatically.
Use Discount % = (Original − Sale) / Original × 100. A $480 item now selling for $336 is (480 − 336) / 480 × 100 = 30%. The Find Discount % mode shows this directly when you enter both prices.
It means 50% is the maximum discount on any item in the promotion, not the discount on every item. Most products will be marked down less. Check each item's actual sale price against its original price in Find Discount % mode to see what you're really getting.
Markup is the percentage added to cost to get the selling price (a $50 cost sold for $75 has a 50% markup). Margin is the profit as a percentage of selling price (that same item has a 33.3% margin). Both describe the same dollar gap but use different denominators — important when reading retail or pricing reports.
Buy 2 get 1 free equals 33.3% off when you actually need all three items, since you pay for two and receive three. It beats a flat 30%. If you'd only have bought one or two items, a flat 30% across the board is usually the better deal.
BOGO 50% off means the second item is half price, so on two equally priced items you pay 100% + 50% = 150% for two units instead of 200%. That's a 25% discount on the pair total, not 50%.
No. It computes only the markdown on the item itself. Shipping, restocking fees, and taxes are applied separately by the merchant. Add them after to compare two offers on out-the-door cost.
The badge is computed from the actual numbers you entered, not from a preset. If the original and sale price don't line up to a clean percentage (for example, $479 to $336), the calculator shows the true rate to one decimal place rather than rounding it to the nearest tag.
Sale price uses Sale = Original × (1 − Discount/100); savings = Original − Sale; reverse mode uses Discount % = (Original − Sale) / Original × 100 and Original = Sale / (1 − Discount/100). The discount input is capped internally at 99.99% to avoid division by zero in reverse mode. Stacked discounts in worked examples follow the multiplicative rule 1 − (1 − d₁)(1 − d₂). Sales tax and shipping are excluded from the markdown math and shown separately in worked examples for context only.
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