Discount Calculator with GST
Enter an MRP and a discount — as a percentage or a flat amount — to see the saving and the final price. Flip on GST and the tax lands on the discounted value, the way it should.
GST is charged on what the customer actually pays, so the tax is worked out on the post-discount value — not on the MRP.
Discounts and GST, done right
A discount is simple arithmetic until tax gets involved. Get the order of operations wrong and you either overcharge the customer or short-pay the department.
Discount first, tax after
GST applies to the transaction value — the amount the customer actually parts with. Knock the discount off first, then compute tax on what is left. Taxing the MRP and then discounting the total gives a different, wrong answer.
Show it on the invoice
The deduction only holds if the discount appears on the face of the invoice and was agreed at or before the sale. Handshake discounts settled later need a credit note, and the buyer has to reverse the matching input tax credit.
Stacked offers compound
“40% off plus an extra 10%” is 46% off, not 50%. Each discount works on the balance left by the one before it. Handy when you are designing an offer — the headline reads bigger than it costs you.
The maths
- Saving: list price × discount ÷ 100.
- Final price: list price − saving.
- Effective %: saving ÷ list price × 100.
- GST: final price × rate ÷ 100, split into CGST + SGST within a state.
- Two discounts: combined = 100 − (100 − a) × (100 − b) ÷ 100.
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- Unlimited business profiles & store locations
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Discount calculator FAQ
Multiply the list price by the discount percentage and divide by 100 to get the rupees you save, then subtract that from the list price. A 20% discount on ₹2,499 is ₹499.80 off, leaving ₹1,999.20. To work backwards from a flat rupee discount, divide the saving by the list price and multiply by 100 — switch this calculator to "Flat amount" and it shows you the effective percentage.