A 30% markdown plus an "extra 20% off" rack sign sounds like 50% off — but it is not. Stacked discounts compound on the already-reduced price, and once sales tax is added the true out-the-door number is almost never the one on the tag. This clearance price calculator walks through every layer — markdown, extra off, flat coupon, tax, and quantity — so you know exactly what you will pay and exactly how much you saved before you open your wallet.
Type into the boxes and every figure updates instantly. Compare two scenarios side by side by changing the extra-off slider, and use the result card to see the effective discount percentage — the single number that tells you whether the "sale" is actually a deal.
How to Use
- Enter the Original Price — the ticketed price, MSRP, or price before the store put up a red tag.
- Set the Markdown % — the first discount printed on the shelf sign (for example 30% off).
- Add an Extra Off % if there is a second coupon, clearance flyer, member discount, or "take an extra X% off" pile. This discount stacks on the markdown price, not on the original.
- Type your Sales Tax rate. Use your combined state-and-local rate; leave at 0 if your purchase is tax-exempt or you are shipping to an untaxed state.
- Optionally enter a flat Coupon ($ off) — a paper coupon, a loyalty reward, or a gift-card balance. It is subtracted last, after all percentage discounts.
- Set the Quantity if you are buying more than one identical clearance item.
The result card then shows the price after the markdown, the price after the extra-off layer, the discounted subtotal, the tax, the total you actually pay, and the total dollar savings — plus the effective discount percentage, which combines every layer into one comparable number.
How Stacked Discounts Actually Work
The biggest clearance-math mistake is adding percentages. A 30% markdown followed by an extra 20% off is not 50% off, because the extra 20% is taken off the already-reduced price:
- Start at $200.
- 30% markdown: 200 × (1 − 0.30) = $140.
- Extra 20% off that $140: 140 × (1 − 0.20) = $112.
- The customer saved $88 off the first layer and $28 off the second, for a discounted price of $112.
- That is an effective discount of $88 ÷ $200 = 44%, not 50%.
The formula chain is:
afterMarkdown = originalPrice × (1 − markdownPercent ÷ 100) afterExtra = afterMarkdown × (1 − extraOffPercent ÷ 100) subtotal = max(afterExtra × quantity − couponAmount, 0) total = subtotal × (1 + taxRate ÷ 100) savings = originalPrice × quantity − total
Tax is charged on the discounted subtotal, which is exactly how every US retailer operates: the customer pays tax on the money actually spent, not on the phantom price that was crossed out.
Markdown vs. Coupon: Order Matters
When a store offers both a percent-off and a flat-dollar coupon, the order in which they are applied changes the final price by a few dollars. The universal retail rule is percent discounts first, flat coupons last:
- On a $100 item at 30% off, then a $10 coupon: $70 − $10 = $60.
- With the $10 coupon first, then 30%: $90 × 0.70 = $63.
Applying the percentage first gives you the lower price, because the percent discount then works on a smaller base. Almost every point-of-sale system already does this in your favor, but it is worth knowing if you are stacking two coupons manually.
Examples
Example 1 — The headline deal. An original price of $200, a 30% markdown, an extra 20% off clearance, and 8% sales tax. After the markdown the price is $140; after the extra off it is $112; tax adds $8.96; the out-the-door total is $120.96. Total savings versus the original price are $79.04, an effective discount of about 39.5%.
Example 2 — Big-ticket clearance. A floor lamp originally priced at $1,000, marked down 50%, with an extra 10% off the clearance rack and no tax. After the markdown: $500. After the extra 10%: $450. You pay $450.00 and save $550.00 — an effective 55% discount. Running the same math at $1,000,000 of wholesale inventory (50% markdown + 10% extra off) still lands at $450,000, so the engine scales cleanly to large wholesale liquidation buys.
Example 3 — Coupon on top. A $80 jacket on a 25% rack, plus a $15 birthday coupon, 7% tax. After markdown: $60. After coupon: $45. Tax at 7%: $3.15. Total paid: $48.15, savings $31.85.
FAQ
Are 30% off plus extra 20% off equal to 50% off?
No. The extra 20% is applied to the already-discounted price, not the original. On a $200 item, 30% off leaves $140, and 20% off of $140 leaves $112 — an effective 44% discount, not 50%. Use the Effective Discount row on the result card to see the true combined percentage.
Is sales tax calculated before or after the discount?
After. Retailers in the United States charge sales tax on the final discounted price the customer actually pays, not on the original ticketed price. This calculator applies tax to the discounted subtotal, which matches how checkout registers work.
Can I stack more than two discounts?
Yes in spirit, but the calculator models the two most common layers — a shelf markdown and an extra-off promotion. If you have three or more percent discounts, apply them one at a time by hand (each new discount multiplies the current price by (1 − percent/100)) or enter the combined extra-off percentage as one number for a close approximation.
Does a dollar coupon come before or after a percent discount?
Stores almost always apply percentage discounts first and flat-dollar coupons last, which gives the customer the lower price. On a $100 item at 30% off, then a $10 coupon, you pay $60; reversing the order gives $63. This calculator follows the standard retail order.
What is a good clearance discount percentage to look for?
Anything above 40% off the original price is a strong clearance, above 60% is a steep one, and 70% or more usually signals the store is making room for new inventory — the best time to buy. Beware of "fake clearance" where the original price was marked up for a week then reduced; check price history before you pull the trigger.
What happens if the discounted price goes below zero?
If your coupons and discounts pile up past the item's price, the subtotal is floored at $0.00 — you cannot be charged a negative price, and the store does not owe you money for the item. Sales tax on a $0 subtotal is $0.
Is the effective discount the same as the headline markdown?
No. The headline markdown is just the first layer. The effective discount blends markdown, extra-off, coupon, quantity, and tax into one number against the original price — that is the figure to compare against competing stores and price-history charts.
Disclaimer
This clearance price calculator is provided for informational purposes only and does not constitute financial, tax, or retail advice. Discount stacking, coupon compatibility, and tax treatment vary by retailer, state, and promotion; actual checkout prices may differ due to manager discounts, loyalty rewards, membership pricing, or returns policy. Always confirm your final total at the register or online checkout before buying.