How to Calculate a Discount
Calculating discounts is an essential skill for smart shopping. Whether it's seasonal sales, Black Friday, or clearance events, knowing exactly how much you save helps you make better decisions.
Discount Formulas
Calculate the discounted price
Final price = Original price × (1 - Discount/100)
Example: A $200 product with 30% off: $200 × (1 - 0.30) = $200 × 0.70 = $140
Find the discount percentage
Discount % = ((Original price - Final price) / Original price) × 100
Example: A product dropped from $150 to $105: ((150 - 105) / 150) × 100 = 30%
Find the original price
Original price = Final price / (1 - Discount/100)
Example: You paid $80 with a 20% discount: $80 / (1 - 0.20) = $80 / 0.80 = $100
Tips for Getting the Best Deals
- Always compare the original price before getting excited about the percentage
- Calculate real savings in money, not just percentage
- Stacking discounts: 20% + 10% extra is not 30% — it's 28% total
- Unit price: sometimes the "discount" on bulk isn't the best deal
Compound Discounts
When discounts are applied successively (e.g., 20% + 10% extra), they multiply:
Final price = Original × (1 - 0.20) × (1 - 0.10) = Original × 0.72
This equals a 28% total discount, not 30%.