Discount Calculator: Sale Price, Discount % and Successive Discounts
Find the price after any discount, the discount % between two prices, or the original price behind a sale price. Stack extra discounts (20% + 10% = 28%), compare % off, flat ₹ off and buy X get Y offers, see how GST applies to a discount, check what a discount does to your margin, and total a cart or print a sale price list for your shop. In English or Hindi, free and with no sign-up.
By ScaleSaathi Editorial · GST rules last checked 22 Oct 2026 · Sources
Before you trust the “% off” on the tag
- Extra discounts don’t add up. 20% + 10% off is 28% off, not 30%, because the second discount is taken on the already reduced price.
- Buy 2 get 1 free is worth 33.33% off only if you actually take 3 items. An “up to ₹500” offer stops growing once the cap is reached.
- GST follows the invoice. A discount shown on the invoice at or before the sale comes off the taxable value (CGST Act section 15(3)). Example from the page: ₹1,180 MRP including 18% GST with 10% off, you pay ₹1,062. GST rules last checked 22 Oct 2026.
- Sellers lose more than the discount. In the page’s example a 28% discount cuts the margin from 43.34% to 21.3%, and profit falls 64.61%.
Discount Calculator
Sale price, discount %, original price, extra discounts, offer comparison, GST and your margin. Free, no sign-up, runs in your browser.
1. Price and discount
2. GST on the bill
3. Seller: effect on your margin (optional)
Paste from Excel or Google Sheets
How to use the discount calculator
- Price after discount: enter the MRP, the quantity and the discount (% or flat ₹). Add an “up to ₹…” limit or extra discounts if the offer has them.
- Optional: pick the GST rate, whether the price includes GST, and when the discount is given.
- Seller? Open Effect on your margin and enter your cost and the lowest margin you accept.
- Use Find discount % for two prices, Find original price to work back from a sale price, Compare offers for % vs flat vs buy X get Y, and Cart and sale price list for a whole bill or a printed shop list.
Discount formulas
| What | Formula | Example |
|---|---|---|
| Discount amount | Price × discount % ÷ 100 | ₹2,000 × 20 ÷ 100 = ₹400 |
| Price after discount | Price × (1 − discount %) | ₹2,000 × 0.8 = ₹1,600 |
| Discount % from two prices | (Original − sale) ÷ original × 100 | (2,000 − 1,600) ÷ 2,000 = 20% |
| Original price from sale price | Sale price ÷ (1 − discount %) | ₹1,600 ÷ 0.8 = ₹2,000 |
| Successive discounts a% + b% | 1 − (1 − a)(1 − b) | 20% + 10% = 28% |
| Buy X get Y free | Y ÷ (X + Y) | Buy 2 get 1 = 33.33% |
Successive (double) discounts
When a shop offers 20% off and then 10% extra, the second discount is taken on the reduced price. The total is 1 − 0.8 × 0.9 = 0.28, or 28%, not 30%. The order does not matter.
| Discounts | Single equivalent discount |
|---|---|
| 10% + 10% | 19% |
| 10% + 20% | 28% |
| 20% + 10% | 28% |
| 25% + 10% | 32.5% |
| 20% + 20% | 36% |
| 30% + 20% | 44% |
| 30% + 40% | 58% |
| 50% + 20% | 60% |
| 20% + 15% + 10% | 38.8% |
% off, flat ₹ off or buy X get Y?
Which offer is cheaper depends on how much you buy. Buy 2 get 1 free is 33.33% off only if you take 3; a flat ₹ off is worth more on a small bill; a % off “up to ₹500” stops growing once the cap is reached. Enter up to three offers in Compare offers and the cheapest for your quantity is marked.
GST and discounts
Under CGST Act section 15(3), a discount is left out of the taxable value if it is given before or at the time of supply and recorded on the invoice. A discount given after the sale is left out only if it was agreed at or before the sale, is linked to the invoices, and the buyer reverses the matching input tax credit. The Finance Act, 2026 (section 153) replaces that second test with a credit note under section 34, but the change applies only from a date the Central Government notifies (Gazette). Example: ₹1,180 MRP including 18% GST with 10% off:
| When the discount is given | GST is charged on | Taxable value | GST | Customer pays |
|---|---|---|---|---|
| On the invoice, at or before the sale | Price after discount (s.15(3)(a)) | ₹900 | ₹162 | ₹1,062 |
| After the sale, s.15(3)(b) conditions met | Price after discount | ₹900 | ₹162 | ₹1,062 |
| After the sale, conditions not met | Original value | ₹1,000 | ₹180 (seller bears ₹18 extra) | ₹1,062 |
To split GST into CGST and SGST or IGST, use the GST calculator; to issue the bill with the discount shown, use the GST bill maker.
Worked example: what a discount does to a seller's margin
| Line | Amount |
|---|---|
| MRP (incl. 18% GST) × 2 | ₹4,998.00 |
| 20% off, then 10% extra | ₹1,799.28 each (28% in total) |
| Total to pay / you save | ₹3,598.56 / ₹1,399.44 |
| Taxable value and GST on the invoice | ₹3,049.63 + ₹548.93 |
| Seller's cost ₹1,200 each | ₹2,400.00 |
| Margin before → after discount | 43.34% → 21.3% |
| Profit before → after | ₹1,835.59 → ₹649.63 (−64.61%) |
| Largest discount that keeps a 25% margin | 24.45% |
A 28% discount more than halves the margin, because the cost stays the same. To include marketplace fees, shipping and break-even units, use the profit margin calculator.
Cart totals and a printable sale price list
For a shop bill, add each item's MRP, discount and quantity, then any extra bill discount % and flat coupon. The calculator shows the MRP total, every discount, the total to pay, the saving and the GST inside the bill. For a sale, add your shop name and sale title and print a price list showing the MRP struck through, the offer and the sale price. Paste items from Excel or download them as CSV.
हिन्दी में: डिस्काउंट कैसे निकालें
छूट = MRP × छूट % ÷ 100। छूट के बाद कीमत = MRP − छूट। डिस्काउंट % = (MRP − सेल कीमत) ÷ MRP × 100। दो छूट (जैसे 20% + 10%) एक के बाद एक लगती हैं, इसलिए कुल 28% होती है, 30% नहीं। बिल पर दिखाई गई छूट के बाद की कीमत पर ही GST लगता है। कैलकुलेटर के ऊपर हिन्दी बटन दबाकर पूरा टूल हिन्दी में इस्तेमाल करें।
Compared with other discount calculators
What other discount calculators often miss:
| Feature | Typical calculator page | ScaleSaathi |
|---|---|---|
| Price after discount and amount saved | All | Yes |
| Discount % from two prices; original price from sale price | Some (often separate pages) | Both, in tabs |
| Successive discounts with the single equivalent % | About half | Up to 6 discounts, step by step |
| “Up to ₹…” caps, flat ₹ off, minimum spend, buy X get Y | Rare, one or two types at most | All, side by side in Compare offers, with the best one marked |
| GST before or after discount (invoice vs post-sale, s.15(3)) | A few explain it in a line; none models post-sale discounts | Yes, three cases with the law cited |
| Seller margin and largest safe discount | Rare | Yes, with a link to the profit margin calculator |
| Multi-item cart with bill discount and coupon | One (Zoho) in our sample | Yes, up to 300 items, paste from Excel, CSV |
| Printable sale price list for a shop | None found | Yes |
| Hindi | One site has a Hindi version | Full Hindi interface and Hindi FAQ |
| Sign-up prompts | Two of the bigger brands | None |
Frequently asked questions
How do I calculate a discount?
Discount amount = original price × discount % ÷ 100, and price after discount = original price − discount amount. Example: 20% off ₹2,499 is ₹499.80 off, so you pay ₹1,999.20. A quick way: multiply the price by (100 − discount) ÷ 100, so 20% off means × 0.8.
How do I calculate the discount percentage from two prices?
Discount % = (original price − sale price) ÷ original price × 100. Example: MRP ₹1,999 and sale price ₹1,399 gives 600 ÷ 1,999 × 100 = 30.02% off. Use the Find discount % tab.
How do I find the original price from the sale price?
Original price = sale price ÷ (1 − discount %). Example: ₹1,600 after 20% off was ₹1,600 ÷ 0.8 = ₹2,000. For two discounts such as 20% + 10%, divide by 0.8 and then by 0.9: ₹1,440 ÷ 0.72 = ₹2,000. Use the Find original price tab and type 20+10.
How is a successive discount calculated?
Apply each discount to the price left after the one before. The single equivalent discount = 1 − (1 − a)(1 − b), or a + b − ab ÷ 100. So 20% + 10% = 28%, 10% + 20% = 28%, 25% + 10% = 32.5%, 30% + 40% = 58%, and 20%, 15% and 10% together = 38.8%. Successive discounts are always less than their sum.
Is 20% + 10% the same as 30% off?
No. 20% + 10% extra is 28% off. On ₹1,000 you pay ₹800 after 20%, then 10% of ₹800 = ₹80 more, so ₹720. A straight 30% off would be ₹700.
What does “buy 2 get 1 free” work out to?
You pay for 2 of every 3 items, so it is 33.33% off when you take 3. If you take only 2 items you get no discount. Compare it with a % or flat offer in the Compare offers tab: at ₹499 an item, buy 2 get 1 free costs ₹998 for 3, against ₹1,047.90 at 30% off.
Which is better: a % discount or a flat ₹ off?
A flat ₹ off is worth more on small bills and a % discount on large ones. They are equal when bill × % ÷ 100 = the flat amount: ₹400 off equals 20% off on a ₹2,000 bill. Also check “up to” caps and minimum spend. Enter both in Compare offers to see the cheaper one for your quantity.
Is GST charged before or after the discount?
If the discount is shown on the invoice at or before the sale, GST is charged on the price after discount: CGST Act section 15(3)(a) excludes such a discount from the value of supply. On an MRP of ₹1,180 including 18% GST with 10% off, you pay ₹1,062, of which ₹900 is the taxable value and ₹162 is GST.
What about discounts given after the sale?
A discount given after the sale is excluded from the taxable value only under section 15(3)(b): today the discount must be set by an agreement made at or before the sale and linked to the invoices, and the buyer must reverse the matching input tax credit. The Finance Act, 2026 replaces this with a credit-note test under section 34, but that change comes into force only on a date the Government notifies. If the conditions are not met, GST stays on the original value and the seller bears it. Pick “When the discount is given” to see the effect.
How much margin do I lose when I give a discount?
More than the discount. Because your cost stays the same, a 28% discount on a product with a 43.34% margin cuts the margin to 21.3% and the profit by 64.61% in the example on this page. Enter your cost and minimum margin to see the largest discount you can afford, or use our profit margin calculator for fees and break-even.
Can I make a sale price list for my shop?
Yes. In Cart and sale price list, add items with MRP and discount % (or paste them from Excel), add your shop name and sale title, and click Print sale price list. It prints the MRP struck through, the offer, the sale price and the saving for each item. You can also download it as CSV.
Can I calculate the total discount on a cart of many items?
Yes. Add each item with its MRP, discount % and quantity, plus any extra bill discount % and a flat coupon. You see the MRP total, each discount, the total to pay, your saving and the GST included in the bill. Bill-level discounts are shared across items by value.
What does “up to ₹500 off” mean?
The % discount stops at that amount. 50% off up to ₹500 on a ₹2,000 item gives only ₹500 off (25%), not ₹1,000. Enter the limit in the “Maximum discount per item” box or in an offer's Max ₹ field.
Is this discount calculator free and private?
It is free with no sign-up. Every calculation runs in your browser and nothing is uploaded. Copy link to this calculation stores your inputs in the page address so you can bookmark or share them yourself.
Discount kaise nikale? (डिस्काउंट कैसे निकालें)
छूट = कीमत × छूट % ÷ 100। 1000 का 20% = ₹200, यानी आप ₹800 देंगे। 500 पर 20% डिस्काउंट = ₹100 छूट, कीमत ₹400। 300 का 10% = ₹30। डिस्काउंट % = (MRP − सेल कीमत) ÷ MRP × 100। कैलकुलेटर में हिन्दी बटन दबाकर हिन्दी में इस्तेमाल करें।
Sources
GST law last checked 22 October 2026 on official sites. Confirm current rules with your tax adviser.
- CBIC: CGST Act, 2017 (s.15 value of supply; s.15(3) discounts; s.34 credit notes)
- Gazette of India: Finance Act, 2026, s.1(2)(b) and s.153 (new s.15(3)(b), to come into force on a notified date)
- CBIC FAQ on GST (pre- and post-supply discounts)
- PIB: GST rates 5%, 18% and 40% from 22 Sep 2025
More free tools: all calculators · profit margin calculator · GST calculator · GST bill maker
This calculator does arithmetic on the figures you enter and is not tax advice.