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"Flat 50% + Extra 20% Off": What You Really Save
By Quick Work Studio · Published 29 October 2026 · How we check facts
Sale banners love stacked numbers: "Flat 50% + Extra 20% Off", "Buy 2 Get 1 Free", "Up to 70% Off", "10% Instant Discount with Bank Cards". Each of these means something precise, and it's often less than it looks. A little maths shows what you actually pay.
Two discounts don't add up
"Flat 50% + extra 20%" sounds like 70% off. It isn't. The extra 20% is taken from the price after the first discount, not from the original price.
- A shirt costs ₹2,000. Flat 50% off brings it to ₹1,000.
- Extra 20% off ₹1,000 is ₹200, so you pay ₹800.
- ₹800 out of ₹2,000 is 40% of the price, so the real discount is 60%.
The quick formula: multiply what's left after each discount. 50% off leaves 0.5, 20% off leaves 0.8, and 0.5 × 0.8 = 0.4. You pay 40%, so you save 60%.
| Offer | Sounds like | Real discount |
|---|---|---|
| 50% + 20% | 70% | 60% |
| 40% + 10% | 50% | 46% |
| 60% + 30% | 90% | 72% |
| 30% + 20% + 10% | 60% | 49.6% |
| 70% + 10% | 80% | 73% |
The order doesn't matter: 20% then 50% gives the same ₹800.
"Buy 2 Get 1 Free" and "Buy 1 Get 1"
- Buy 2 Get 1 Free: you pay for 2 and take 3, so you pay two-thirds. That's a 33.3% discount, but only if you actually wanted three.
- Buy 1 Get 1 Free: 50% off per item, again only if you'd have bought two anyway.
- Buy 3 for ₹999: compare with the single price. If one costs ₹399, three would be ₹1,197, so you save ₹198, about 16.5%.
If you didn't need the extra item, a "free" item is just a reason to spend more. A simple 30% off on the one thing you need is often better.
"Up to 70% off"
"Up to" means at least one item somewhere in the sale has 70% off. Most items may have 10% to 30%. Check the price tag of the item you want, not the banner.
Bank offers and their caps
"10% instant discount up to ₹1,500" has a ceiling. On a ₹10,000 purchase you save ₹1,000 (10%). On ₹40,000, 10% would be ₹4,000, but you get only ₹1,500, which is 3.75%. Bank offers also often need a minimum purchase and apply to specific cards, and EMI offers may have a processing fee that eats into the saving.
Flat ₹ off vs % off
"₹500 off" on a ₹2,000 item is 25% off. On a ₹10,000 item it's only 5%. To compare a rupee discount with a percentage, divide the rupees off by the price and multiply by 100.
Cashback is not a discount
Cashback comes later, often as wallet balance or a coupon you can only use on the same site, sometimes with an expiry date. ₹200 cashback that you'll use is worth something; one you'll forget is worth nothing. Compare offers by the money that actually leaves your account today.
Is the "original price" real?
In India the MRP printed on packaged goods includes all taxes, and a shop can't charge more than the MRP. But a sale's "original price" online can be inflated just before a sale to make the discount look bigger. If it's a big purchase, look at what the same item sold for a few weeks earlier.
Working backwards: what was the price?
If you know the sale price and the discount, divide the sale price by what's left. A sale price of ₹1,200 after 40% off means the original was ₹1,200 ÷ 0.6 = ₹2,000.
Comparing packs and sizes
A bigger pack on discount isn't always cheaper per gram. Divide the price by the quantity for each option, or use the Unit Price Comparator, which does it for several packs at once. Our guide on which pack is cheaper has more examples.
Try it: the Discount Calculator shows the final price and your saving for any discount, and the Percentage Calculator handles the reverse sums. For GST-inclusive and exclusive prices, use the GST Calculator.