E-commerce thrives on the gap between displayed savings and actual savings. A "70% off + 20% extra" sticker is not 90% off — it's 76%. A "MRP ₹2,499, deal price ₹999" is not 60% off — once you remove GST from both sides, it's closer to 55%. The discount calculator handles all of this.
Open the Discount Calculator and use it the next time you see a sale.
Stacked discounts: the multiplication rule
Stacked percentage discounts multiply, they don't add. Two discounts of a% and b% together produce a final discount of:
combined = 1 − (1 − a/100) × (1 − b/100)
| Sticker math | Actual math |
|---|---|
| 70% + 20% = 90% | 1 − 0.30 × 0.80 = 76% |
| 50% + 50% = 100% | 1 − 0.50 × 0.50 = 75% |
| 30% + 10% = 40% | 1 − 0.70 × 0.90 = 37% |
The bigger the stack, the bigger the gap. The "100% off" version is the classic giveaway that the math isn't additive — if it were, two 50% discounts would make everything free.
The four modes the calculator supports
- Find the discount — original price → discounted price → what % savings is that?
- Find the final price — original price → discount % → what do I pay?
- Find the original price — final price → discount % → what was the pre-sale price? (Useful for spotting fake discounts.)
- Stacked discounts — original price + list of discount %s → final price + effective single %
The MRP-vs-deal-price trick
In India, MRP is maximum retail price. Many products carry an MRP printed at 2–3× the realistic retail price specifically to make every "deal" look like a steep discount. The fix: compare with the price across multiple sellers, not against the MRP.
When the discount is real and worth taking
- Year-end sales (Dec–Jan, Mar): genuine inventory clearance, deepest cuts
- Festive (Big Billion / Great Indian): usually real on electronics, often fake on apparel
- Coupon-stack windows during launches: bank offer + card offer + first-purchase code can stack to real 30–40% off on premium items
Run yours
Open the Discount Calculator. Punch in the stickers. Decide with the actual number, not the marketing one.
