How to Calculate Discount Price – Formula, Examples & Tips
Getting the best deal on a purchase, verifying a sale price, or calculating the final cost including GST — all require knowing how to calculate discount price accurately. This guide covers flat discounts, percentage discounts, combined discounts, and GST-on-discounted-price calculations common in Indian retail.
What is a Discount?
A discount is a reduction from the original price. In retail, discounts are used to attract buyers, clear inventory, reward loyal customers, or match competitor pricing. There are two main types: flat discounts (₹X off) and percentage discounts (Y% off). During sale seasons in India — Big Billion Day, Amazon Great Indian Festival, Republic Day sales — understanding how discounts are calculated prevents being misled.
Formula: Percentage Discount
Sale Price = Original Price − Discount Amount
Or combined: Sale Price = Original Price × (1 − Discount%/100)
Step-by-Step Example
A smartphone priced at ₹32,999 is on 15% discount.
- Discount Amount = ₹32,999 × (15/100) = ₹32,999 × 0.15 = ₹4,950
- Sale Price = ₹32,999 − ₹4,950 = ₹28,049
- Or directly: ₹32,999 × 0.85 = ₹28,049
Calculating Discount Percentage (When You Know Both Prices)
Example: A bag was ₹4,500, now ₹3,150. Discount % = ((4,500-3,150)/4,500) × 100 = 30%
Successive (Stacked) Discounts
When two discounts are applied one after another (e.g., 20% then 10% for using a credit card):
- Price after first discount: ₹10,000 × (1 - 20/100) = ₹8,000
- Price after second discount: ₹8,000 × (1 - 10/100) = ₹7,200
- Equivalent single discount = ((10,000 - 7,200) / 10,000) × 100 = 28% (not 30%!)
Discount + GST Calculation
In India, GST applies on the discounted price (post-discount base price), not the MRP.
Example: ₹5,000 product, 20% discount, 18% GST:
- Discounted Price = ₹5,000 × 0.80 = ₹4,000
- GST Amount = ₹4,000 × 0.18 = ₹720
- Final Price = ₹4,000 + ₹720 = ₹4,720
Common Mistakes to Avoid
- Applying two discounts additively (20% + 10% ≠ 30% — it's 28%).
- Forgetting that "30% off" on a product where MRP was already inflated doesn't mean a real 30% saving.
- Not checking if the discount is on MRP (Maximum Retail Price) or on a "crossed-out" artificially high price.
Frequently Asked Questions
Is GST calculated on the original price or discounted price?
As per CBIC guidelines, GST is charged on the transaction price (the discounted price), not the MRP. So a genuine discount effectively also reduces the GST amount payable.
How do I find original price from sale price and discount?
Original Price = Sale Price / (1 − Discount%/100). Example: Sale price ₹2,100 after 30% off → Original = ₹2,100 / 0.70 = ₹3,000.
🔢 Try these: Discount Calculator, GST Calculator, Percentage of Number.