Calculate sale prices, savings, original prices, and discount percentages instantly.
This free discount calculator lets you calculate sale prices, discount amounts, total savings, original prices, and discount percentages instantly — all in one tool with three calculation modes. Whether you're a shopper working out how much you save on a 30% off deal, a retailer setting markdown prices, or a student checking a maths problem, this tool handles every discount scenario in seconds with no signup required.
Discount calculations come up constantly in everyday life — at the checkout, comparing deals online, working out if a sale is genuine, or pricing your own products and services. Despite being simple in principle, discount maths trips people up regularly: two successive discounts are not simply added, a bigger percentage doesn't always mean a better deal in absolute terms, and working backwards from a sale price to find the original requires a division, not a subtraction. This calculator handles all three directions precisely.
The tool offers three modes: Sale Price (enter original price + discount % to get the final price and savings), Find Original Price (enter the sale price and discount % to reverse-calculate what the item originally cost), and Find Discount % (enter both prices to find out exactly what percentage off you received).
Enter the original price and the discount percentage. Use the quick-select buttons for common discounts (10%, 20%, 25%, 50%) or type any value. Results update live as you type: you see the discount amount, the sale price, how much you save, and the effective percentage you're paying of the original price. This is the mode to use at the checkout or while comparing sale items online.
Enter the discounted sale price and the discount percentage that was applied. The calculator works backwards to reveal the original pre-discount price. This is useful for verifying whether a "sale" is genuine — if the original price calculated seems suspiciously high, the discount may be based on an inflated RRP rather than the real regular selling price.
Enter both the original price and the final sale price. The calculator tells you the exact percentage discount, the absolute saving in dollars, and confirms the amount paid. Use this when a shop advertises a flat dollar discount ("$30 off!") and you want to know if that percentage is actually competitive. It's also useful for comparing discounts across items with different original prices.
Run the calculator on each deal you're comparing. For items sold in different quantities or sizes, note the price-per-unit after discount to make a true apples-to-apples comparison. A 500g product with 20% off at $4.00 costs $3.20 (64c/100g). A 750g product with 10% off at $4.50 costs $4.05 (54c/100g) — a better deal per gram despite the smaller discount percentage.
Most discount calculators only calculate forward — original price minus percentage. This tool also reverse-calculates: find the original price from a sale price, or find what percentage off you actually got. Three modes cover every discount scenario you'll encounter as a shopper, retailer, or student.
Results update in real time with every keystroke. There's no Calculate button to press — just type your values and the discount amount, sale price, and savings appear instantly. This makes it fast to test multiple scenarios back-to-back without clearing and re-entering data.
One-tap buttons for the most common discount percentages — 5%, 10%, 15%, 20%, 25%, 30%, 40%, 50%, and 70% — let you instantly apply standard discounts without typing. Tap a button and the discount field populates automatically, updating results in the same instant.
Results show the complete picture: original price, discount amount, sale price, total savings, and the effective percentage of the original price you're paying. This full breakdown prevents the common mistake of confusing the discount amount with the final price — everything is labelled clearly.
Fully responsive on iPhone, Android, tablet, and desktop. Use it in the shop aisle on your phone to quickly verify a deal before buying, or on desktop to compare multiple online offers side by side. No app to install, no account to create.
All calculations happen locally in your browser. The prices you enter are never sent to our servers or stored anywhere. Your shopping habits and spending data stay completely private. This tool does not use cookies for tracking or analytics beyond standard page analytics.
Understanding the underlying maths helps you calculate discounts mentally and verify results. Here are all the formulas this tool uses, with worked examples.
| What You Want | Formula | Example | Result |
|---|---|---|---|
| Discount Amount | Original × (Discount% ÷ 100) | $120 × (25 ÷ 100) | $30.00 |
| Sale Price | Original − Discount Amount | $120 − $30 | $90.00 |
| Sale Price (shortcut) | Original × (1 − Discount%/100) | $120 × 0.75 | $90.00 |
| Savings | Original − Sale Price | $120 − $90 | $30.00 |
| Original Price | Sale Price ÷ (1 − Discount%/100) | $90 ÷ 0.75 | $120.00 |
| Discount Percentage | ((Original − Sale) ÷ Original) × 100 | ((120−90) ÷ 120) × 100 | 25% |
| % of Original You Pay | 100 − Discount% | 100 − 25 | 75% |
| Stacked Discounts | Original × (1−D1/100) × (1−D2/100) | $100 × 0.80 × 0.90 | $72.00 (28% off) |
Online retail is driven by discount psychology. Studies consistently show that shoppers respond strongly to percentage-off labels — but that response isn't always rational. A 40% off label on an overpriced item can result in a worse deal than paying full price for a better product elsewhere. Savvy shoppers use a discount calculator to cut through the marketing and focus on two numbers that actually matter: the final price you pay and whether that price is competitive in the market.
When comparing two competing offers — a 25% discount at one store vs a 30% discount at a competitor — the headline percentage alone isn't enough. The item with 25% off might have a lower original price. Always calculate the actual sale price at both retailers and compare those numbers directly. Price comparison apps and browser extensions often use exactly this logic internally.
Black Friday, Cyber Monday, Prime Day, Boxing Day, and seasonal clearance events bombard consumers with percentage-off claims across hundreds of products simultaneously. It's cognitively impossible to manually evaluate every deal. A quick discount calculator on your phone lets you instantly answer the only question that matters at the point of purchase: "What am I actually paying, and is that a good price for this item?"
Sales events also commonly feature multiple layered discounts — "20% off sale prices" applied on top of an already-discounted item. Calculating the effective combined discount requires the stacked discount formula (not simple addition), and the result is usually less than shoppers expect. Our calculator handles this transparently.
Retailers use discount calculations constantly for pricing decisions. Setting a promotional sale price requires working backwards from a target margin: if a product costs $45 to stock and you want to maintain a 30% gross margin while offering a "20% off" promotion, what should the original listed price be? This requires both the reverse-calculation mode and knowledge of cost-plus pricing, not just a simple percentage off calculation.
Small businesses also use discount calculators when negotiating supplier pricing, working out volume discount structures for B2B customers, calculating early payment discounts on invoices (e.g., 2/10 Net 30 — 2% discount if paid within 10 days), and setting end-of-line clearance prices that move stock without unnecessarily deep cuts to margin.
Discount and percentage calculations appear throughout school mathematics curricula — in GCSE Maths, primary school numeracy, and vocational business qualifications. Students use online calculators to check their worked answers and understand where they went wrong. Teachers use them to generate worked examples quickly. The reverse-calculation mode is particularly useful pedagogically because it forces students to think about inverse operations.
Freelancers often need to offer project discounts for new clients, long-term relationships, or volume work. Calculating what a 15% discount on a $2,400 project proposal actually means for the invoice total — and for their effective hourly rate — requires exactly the same discount formula used for retail pricing. The "Find Discount %" mode is useful for checking whether a client's proposed counter-offer represents a reasonable or excessive reduction.
Personal finance apps and budget planners frequently incorporate discount calculations for tracking sale purchases against full-price alternatives, calculating the real cost of loyalty scheme points, evaluating cashback offers ("5% cashback on all purchases" is a 5% effective discount on net spend), and modelling the true cost of financing offers that include promotional pricing periods.
A percentage discount reduces the price by a specified proportion of the original price. "30% off" means you pay 70% of the original price. The absolute saving in dollar terms scales with the price: 30% off a $50 item saves $15; 30% off a $500 item saves $150. Percentage discounts are the most transparent type because they allow direct comparison across items of any price — a 30% off deal is better value than a 25% off deal on equivalent items, regardless of their original prices.
A flat discount subtracts a fixed dollar amount from the price: "$20 off your next purchase." The percentage equivalent varies depending on what you buy. "$20 off a $100 item" is a 20% discount; "$20 off a $400 item" is only a 5% discount. When comparing flat discount offers with percentage discounts, always convert to a consistent basis. The Find Discount % mode in this calculator does this conversion instantly.
Tiered discounts offer increasing percentage savings at higher purchase quantities or spend thresholds. A common B2B structure: buy 1–9 units at full price, 10–49 units at 10% off, 50+ units at 20% off. Calculate the total cost at each tier to find the break-even point — sometimes buying a few extra units to hit the next discount tier costs less total than buying the smaller quantity you actually needed. This is called the "quantity break" calculation.
When two discounts apply to the same item sequentially, they compound rather than add. A 20% trade discount followed by a 10% cash payment discount does not equal 30% off. The calculation is: apply the first discount to get an intermediate price, then apply the second discount to that intermediate price. On a $200 item: 20% off gives $160; then 10% off $160 gives $144. The effective combined discount is 28%, not 30%. This is because the second discount applies to a smaller base price.
Conditional discounts apply only when certain criteria are met: spend over $50 to get 15% off; buy two get one free; members-only pricing; first-order discount codes. "Buy two get one free" on a $15 item means you pay $30 for three items — an effective 33.3% discount on each item. Always calculate the per-unit or total cost under the condition to assess the true discount value.
Common in B2B invoicing, early payment discounts (also called settlement discounts or prompt payment discounts) offer a small percentage reduction — typically 1–3% — for paying an invoice early. A "2/10 Net 30" term means: pay within 10 days and take 2% off; otherwise the full amount is due in 30 days. While 2% sounds small, annualised over 20 days it represents a very high effective interest rate — equivalent to approximately 36% annual interest — making early payment extremely worthwhile for the buyer.
Not all discounts are genuine. Retailers use several tactics to create the perception of savings where little or none exist. Knowing these tactics helps you use a discount calculator to verify claims rather than simply accept them.
This is the most common deceptive practice. A retailer temporarily lists an item at an inflated "original" price — say $200 — then immediately discounts it to $120, advertising "40% off." If the item was never actually sold at $200 in any meaningful volume, the "original price" is artificial and the "40% off" claim is misleading. Many jurisdictions have consumer protection laws requiring that items be sold at the "original" price for a minimum period before being advertised as discounted.
The reverse calculation mode is your defence here: if a retailer shows you a "sale price" and a discount percentage, calculate what the original price should be. Then check independent price history tools (CamelCamelCamel for Amazon, Google Shopping history) to verify whether the item was ever actually sold at that price.
Manufacturers' Recommended Retail Prices (RRPs) or "compare at" prices are sometimes set unrealistically high so that even a normal retail price looks like a discount. A product with an RRP of $150 that retails everywhere at $90 is not genuinely "40% off" at $90 — $90 is its normal market price. Always compare against what the item actually sells for at other retailers, not just the claimed original price.
Bundle offers ("worth $150 — yours for $79") often assign inflated values to individual components to make the bundle's discount appear larger. Calculate whether you'd actually buy each component separately at the stated individual prices. If the individual prices are higher than market value, the "discount" is partly illusory.
| Sale Event | Typical Period | Average Discount Range | Best Categories | Watch Out For |
|---|---|---|---|---|
| Black Friday | Late November | 20–80% off | Electronics, appliances, fashion | Inflated pre-sale prices |
| Cyber Monday | Monday after Black Friday | 15–60% off | Software, tech, online services | Very short-window deals |
| Prime Day (Amazon) | July (2 days) | 10–50% off | Amazon devices, household goods | Prime membership required |
| Boxing Day | December 26 | 20–70% off | Clothing, furniture, Christmas stock | Limited stock sizes/colours |
| End of Season | Jan–Feb, Jul–Aug | 30–70% off | Fashion, outdoor equipment | Limited selection remaining |
| Back to School | August–September | 10–40% off | Electronics, stationery, clothing | Temporary price drops only |
| Singles Day (11/11) | November 11 | 20–60% off | All categories (China-based platforms) | Mostly AliExpress, Shein |
| Flash Sales | Anytime, hours only | 20–50% off | Varies by retailer | Impulse buying pressure |
A 20% discount followed by a 10% discount is not 30% off — it is 28% off. The second discount applies to the already-reduced price, not the original. Always apply each discount sequentially: Original × (1 − D1/100) × (1 − D2/100). Getting this wrong means you'll expect a lower price than you actually receive at the till.
"20% off $50" means the discount amount is $10, and the sale price is $40. Confusing these leads to either expecting to pay just $10 (the discount amount) or thinking you save $40 (the full sale price). Always confirm which number represents what you pay and what you save — the full breakdown in this calculator makes this unambiguous.
In countries with sales tax (USA) or VAT added at the point of sale (rather than included in the displayed price), the discount applies to the pre-tax price. Tax is then calculated on the discounted price. When comparing deals across borders or between tax-inclusive and tax-exclusive retailers, always normalise prices to the same tax basis before comparing.
A 30% discount that saves you $15 on a $50 item is eliminated entirely if the competitor charges $15 shipping while the alternative offers free shipping. Always calculate the total cost delivered — discounted price plus shipping plus any applicable tax — before declaring a deal the winner.
Comparing "40% off Product A" vs "25% off Product B" only makes sense if the original prices are the same. If Product A originally costs $50 (40% off = $30) and Product B originally costs $60 (25% off = $45), Product A is the better deal. Always calculate the actual final price, not just the discount percentage, for a valid comparison.
A product can be shown with a 50% discount while actually being sold at its usual market price — if the "original" price was temporarily inflated before the sale. Use price history tracking tools alongside this calculator to verify that the "original" price represents a real previous selling price, not a manufactured reference point.
Multiply the original price by the discount percentage and divide by 100 to get the discount amount. Subtract that from the original price to get the sale price. Example: 30% off $80 — discount amount = $80 × 30 ÷ 100 = $24. Sale price = $80 − $24 = $56. Or use the shortcut: $80 × (1 − 0.30) = $80 × 0.70 = $56. Enter values above for an instant result.
Divide the sale price by (1 minus the discount rate). If a sale price is $70 after 30% off: $70 ÷ (1 − 0.30) = $70 ÷ 0.70 = $100 original price. Switch to the "Find Original Price" tab in the calculator above and enter the sale price and discount percentage for an instant result.
Subtract the sale price from the original price, divide by the original price, and multiply by 100. Formula: ((Original − Sale) ÷ Original) × 100. Example: item originally $120, bought for $90 — ((120 − 90) ÷ 120) × 100 = 25% off. Use the "Find Discount %" tab in the calculator for instant results.
Apply each discount sequentially, not by adding them. A 20% discount then a 10% discount on a $100 item: $100 × 0.80 = $80 first, then $80 × 0.90 = $72 final price. The effective discount is 28%, not 30%. Stacking two percentage discounts always produces a smaller total discount than their sum.
Discount Amount = Original Price × (Discount % ÷ 100). Sale Price = Original Price − Discount Amount. Savings = Original Price − Sale Price. Original Price = Sale Price ÷ (1 − Discount%/100). Discount % = ((Original − Sale) ÷ Original) × 100. This calculator applies all five formulas automatically depending on which mode you use.
Yes, exactly. Paying after a 40% discount means paying 100% − 40% = 60% of the original price. So $150 with 40% off: $150 × 0.60 = $90. This "pay percentage" shortcut is mathematically equivalent to the standard method and is often faster for mental calculation.
Calculate the final absolute price for both deals, then compare price-per-relevant-unit if items differ in size or quantity. A 40% off $50 item costs $30. A 25% off $36 item costs $27. Despite the smaller percentage, the second is cheaper. For products of different sizes, always divide the final price by the unit quantity (per gram, per litre, per piece) to find the true best value.
A markdown is a permanent reduction in a product's listed retail price — typically for clearance, repositioning, or end-of-life stock. A discount is a temporary price reduction for a promotion, coupon, or sale event. The calculation method is identical; the distinction is whether the price change is permanent (markdown) or temporary (discount). Both are calculated as: Sale Price = Original Price × (1 − Rate/100).
In most jurisdictions, tax is calculated on the discounted (post-discount) price, not the original price. So a $100 item with 20% off and 10% tax: discounted price = $80, tax = $8, total = $88. Some countries (UK, EU) display prices inclusive of VAT, meaning the displayed original and sale prices already include tax. In the USA, displayed prices typically exclude sales tax. Always clarify which basis applies when comparing international deals.
Most retailers allow only one code per transaction. When stacking is permitted, apply each discount sequentially using the compound formula — not by adding percentages. A 20% code and a 10% code stacked give a 28% effective discount, not 30%. Always verify the total price shown at checkout after all codes are applied, regardless of what you expect from mental arithmetic.