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Sale signs shout “25% OFF!” — but what does that actually cost you? A markdown calculator turns any advertised percentage into hard dollars: the price you pay, the money you keep, and the true effective discount. The tool above does exactly that in one step, with no stacked coupons or tax complications, so you can judge every deal on its real numbers.
Here is how to use it:
Pro tip: run the calculator twice for stacked offers — once for the store markdown, then again using the first sale price as the new “list price” for the coupon. A 20% markdown followed by a 10% coupon is not 30% off, and the two-step method shows you the real 28% (worked in Practical Example 2 below).
A markdown is a reduction a retailer makes to an item’s list price (also called the original or ticket price) to arrive at the sale price you actually pay. Markdowns are the store’s own price cuts — clearance events, seasonal sales, and promotional weeks — as distinct from a discount, which often means an extra coupon or code applied at checkout on top of the ticketed price. Both lower what you pay, but they enter the math at different stages, which matters when offers stack.
A few more terms complete the picture. Your savings are the dollar difference between list price and sale price. The effective discount is total savings divided by the list price, expressed as a percentage — the only fair way to compare a $30 saving on $120 against a $30 saving on $300. On the business side, markup is how much the retailer added above cost to set the list price, while margin is the profit left as a share of the selling price. Markdowns eat directly into margin, which is why stores guard them jealously and schedule them strategically.
Retailers use markdowns as a precision tool, not a giveaway. The classic pattern is the planned markdown cadence: new-season goods sell at full price, then take 20–30% off to accelerate turnover, then 40–50% for clearance, and finally 70%+ to liquidate stragglers. Each step trades margin for velocity — freeing shelf space and cash for the next season’s inventory. Flash sales and holiday events (Black Friday, end-of-season) concentrate demand into short windows, while personalized coupons harvest extra margin from price-insensitive shoppers who will not bother clipping them.
Shoppers should also understand the psychology baked into markdowns. A high list price makes the markdown look generous — the “was $200, now $120” anchor — even when $120 was always the intended selling price and the $200 figure was inflated. “Up to 70% off” signs advertise the deepest cut on a handful of items while most of the store sits at 20%. None of this means sales are fake; it means the rational move is to compute the final price and compare it against competing sellers, which is exactly what the calculator above helps you do in seconds.
Markdown math is refreshingly simple — three formulas cover every scenario:
Sale price = list price × (1 − markdown %)
Savings = list price − sale price
Effective discount = savings ÷ list price
Convert the markdown percentage to a decimal first (25% → 0.25). The factor (1 − markdown) is the fraction of the price you still pay — at 25% off, you pay 75%.
Worked example 1. A jacket lists at $120 with a 25% markdown. Sale price = $120 × (1 − 0.25) = $120 × 0.75 = $90.00. Savings = $120 − $90 = $30.00. Effective discount = $30 ÷ $120 = 25.00% — matching the calculator’s result above exactly. With a single markdown, the effective discount always equals the markdown percentage; the metric earns its keep when discounts stack.
Worked example 2. A $250 appliance is marked down 40% for clearance. Sale price = $250 × (1 − 0.40) = $250 × 0.60 = $150.00. Savings = $250 − $150 = $100.00 — a full $100 kept. Effective discount = $100 ÷ $250 = 40%. Notice the symmetry: at 40% off you pay 60%, so a quick mental check is always “what fraction do I still pay?” — 0.6 × $250 = $150.
For stacked discounts, apply each percentage to the running price, not the original: a 20% markdown followed by a 10% coupon on $100 gives $100 × 0.80 = $80, then $80 × 0.90 = $72.00 — total savings $28, effective discount 28%, not 30%. The general rule: multiply the “still pay” fractions (0.80 × 0.90 = 0.72) and subtract from 1. And to work backward from a sale price to the list price, divide: a $90 sale price after 25% off means the list was $90 ÷ 0.75 = $120.
Let us make the widget’s example fully real. The jacket lists at $120, the store markdown is 25%, and your state’s sales tax is 8%.
The calculator gives the pre-tax figures: sale price $90.00, savings $30.00, effective discount 25.00%. Now add tax — which, importantly, is charged on the sale price, not the list price. Tax = $90 × 0.08 = $7.20, so your out-the-door total is $97.20. Had you paid full price, tax would have been $120 × 0.08 = $9.60 for a total of $129.60. Your true all-in saving is $129.60 − $97.20 = $32.40 — the markdown saved you an extra $2.40 in tax you never owed, a small bonus most shoppers never notice.
This example also shows how to sanity-check any deal in seconds: compute the sale price ($90), add tax mentally ($90 + roughly $7), and compare the $97 out-the-door against the item’s price at competing stores. If a rival sells the same jacket for $95 everyday with no sale drama, the “25% OFF” excitement evaporates — the calculator keeps the anchor honest by pinning every claim to dollars.
One more real-world wrinkle: shipping. A $90 sale price with $8 shipping is really a $98 item — an effective discount of only 18.3% off the $120 list. Always add shipping (and subtract any cashback or rewards, say 2% back = $1.80 here) before declaring a deal a winner.
Stacked offers are where markdown math gets interesting — and where stores count on your intuition failing. Take a $100 item with a 20% store markdown plus a 10% coupon at checkout.
Step 1: the markdown brings $100 × 0.80 = $80.00. Step 2: the coupon takes 10% off the sale price: $80 × 0.90 = $72.00. Total savings = $100 − $72 = $28.00, and the effective discount is $28 ÷ $100 = 28% — not the 30% most shoppers assume. The missing 2% is the coupon’s 10% applying to $80 instead of $100. In general, stacked discounts multiply the keep-fractions: 0.80 × 0.90 = 0.72, so you pay 72% and save 28%.
The gap widens with deeper stacks: 40% off plus an extra 25% coupon is not 65% off — it is 1 − (0.60 × 0.75) = 1 − 0.45 = 55% off. On a $200 item that is the difference between a $70 and a $90 final price, a $20 intuition error. Whenever you see “take an extra X% off already-reduced prices,” run the two-step calculation above before celebrating.
From the retailer’s side, stacking is deliberate margin engineering. Suppose the $100 item cost the store $60. At the $72 final price, the gross margin is ($72 − $60) ÷ $72 ≈ 16.7% — thin, but the store moved inventory that was costing shelf space. At only the 20% markdown ($80), margin would have been ($80 − $60) ÷ $80 = 25%. Coupons let stores offer headline-grabbing “extra 10% off” while only shoppers who complete checkout friction actually claim it — precision discounting in action.
1. Adding stacked percentages. 20% + 10% is 28%, not 30%; 40% + 25% is 55%, not 65%. Percentages multiply through the running price — always apply them sequentially or multiply the keep-fractions. This single error causes more overestimated “savings” than any other.
2. Confusing markdown, markup, and margin. A 25% markdown does not mean the store still makes 25%, and a 50% markup does not mean a 50% margin. Markdown is off the list price; margin is profit over the selling price. Mixing them up leads to wildly wrong conclusions about how good a deal really is — for you or the store.
3. Forgetting sales tax (or applying it to the wrong price). Tax applies to the sale price, which slightly sweetens every markdown — but it still adds 5–10% to your out-the-door cost. A $90 deal in a 9% tax state is really $98.10. Budget on the after-tax total, especially for big-ticket items.
4. Anchoring on an inflated list price. “Was $200, now $120” is only a 40% saving if $200 was ever the genuine selling price. Check the item’s price history and competitors: if everyone sells it at $120 everyday, the markdown is theater. Judge deals by the final price versus the market, not versus the anchor.
5. Letting the discount decide the purchase. A 70% markdown on something you would never buy at full price is not saving — it is spending. Pair every deal calculation with the honest question: would I buy this at the sale price if it had never been “on sale”? And compare unit prices ($/oz, $/count) across sizes, because the biggest percentage off is not always the lowest cost per unit.
For discounts that stack coupons on top of sale prices, use the Discount Calculator, which handles multi-layer reductions. For the broader money toolkit — loans, mortgages, investments, and more — browse the full Financial Calculators collection.
Page summary: This page provides a list price markdown calculator. Inputs: list price (dollars), markdown percentage (percent). Outputs: sale price, dollar savings, effective discount percentage. Method: sale price = list × (1 − markdown); savings = list − sale; effective discount = savings ÷ list. Single markdown only — no stacked coupons or taxes. Reference figures: $120 list with 25% markdown → sale price $90.00, savings $30.00, effective discount 25.00%. Scope: percentage-off-list reductions; excludes stacked coupons, sales tax, and shipping.
Sources: standard retail mathematics; U.S. Federal Trade Commission (ftc.gov) guidance on deceptive pricing and “was/now” advertising. Worked-example figures were computed with the formulas above and cross-checked against the calculator widget on this page. Figures rounded to the nearest cent; actual checkout totals vary with tax, shipping, and stacked offers.
Multiply the list price by one minus the markdown: $120 × (1 − 0.25) = $90.00. Try the calculator above.
25% of the list price — $30.00 on a $120 item, leaving a $90.00 sale price.
Total savings divided by the list price. Here it equals the markdown (25.00%), but with stacked discounts it can differ.
A markdown is the store cutting its own list price; a discount is often an extra coupon at checkout. Both lower what you pay.
The sale price — tax is calculated on what you actually pay, so the markdown lowers the tax too.