Why "40% + 10% off" isn't 50% off
Sales often advertise stacked discounts: a flat discount, then an "extra" discount at checkout or with a bank card. The second discount applies to the already reduced price, not to the original, so the total is always less than the two numbers added together.
After first discount = MRP × (1 − d1)
After second discount = that × (1 − d2)
Combined discount = 1 − (1 − d1)(1 − d2)Worked example
Shopping smarter
- Check the MRP and past prices. A "70% off" is only meaningful if the original price was real. Price-history tools and old screenshots help.
- Cashback is not a discount on the spot. It may come as wallet points with an expiry or minimum spend.
- No-cost EMI often means the discount is used to cover interest. You may be able to get the same discount paying upfront.
- Compare the final price per unit across pack sizes; bigger packs aren't always cheaper per gram.
For sellers planning a sale
Discounts come straight out of your margin. On an item with a 40% margin, a 20% discount halves your profit per unit; a 40% discount wipes it out. Enter your cost above to see your margin at the sale price, and use the break-even calculator to see how many extra sales the discount needs to generate just to stay level. Price with room for discounts from the start using the markup calculator.
Discount or free gift?
For sellers, a free add-on that costs you ₹50 but has a ₹150 perceived value often protects margin better than a ₹150 discount. For shoppers, the opposite logic applies: a straight discount is usually worth more than a freebie you didn't plan to buy.
Frequently asked questions
How do I calculate a discount percentage from prices?
Discount % = (original price − sale price) ÷ original price × 100.
Is discount applied before or after GST?
On retail MRP, GST is already included, so the discount applies to the GST-inclusive price. On B2B invoices, trade discounts shown on the invoice are applied before GST.
What does 'buy 1 get 1 free' equal as a discount?
A 50% discount on two items, but only if you actually need both.