🏷️ Discount & Sale Price Calculator
Calculate your final sale price, total dollar savings, stacked double discounts, and checkout price with local sales tax for smart shopping.
| Discount Rate | You Save | You Pay (Before Tax) |
|---|
How to Calculate Discounts?
Calculating a discount helps shoppers determine the exact sale price of an item and verify that store registers are applying markdowns accurately. Whether shopping in-store, online, or taking advantage of Black Friday and Cyber Monday deals, here is how discount mathematics works:
Savings Amount = Original Price × (Discount % ÷ 100)Final Sale Price = Original Price − Savings Amount2. Stacked (Double) Discount Formula:
Price After 1st Discount = Original Price × (1 − (Disc 1 ÷ 100))Final Price = Price After 1st Discount × (1 − (Disc 2 ÷ 100))Total Effective Discount % = 100 × (1 − (1 − Disc1) × (1 − Disc2))
For example, if a jacket originally costs $100.00 with a 30% discount:
- Savings Amount: $100.00 × 0.30 = $30.00
- Final Sale Price: $100.00 − $30.00 = $70.00
The Truth About "Stacked" Discounts (Why 30% + 20% ≠ 50%)
A common misconception during retail promotions is that stacking coupons adds the percentages together (e.g., 30% off clearance plus an extra 20% off coupon). In reality, the second discount is applied to the already reduced price, not the original price.
| Original Price | 1st Discount | Price After 1st | 2nd Discount (20%) | Final Price Paid | True Total Discount |
|---|---|---|---|---|---|
| $100.00 | 20% ($20) | $80.00 | $16.00 | $64.00 | 36.0% (not 40%) |
| $100.00 | 30% ($30) | $70.00 | $14.00 | $56.00 | 44.0% (not 50%) |
| $100.00 | 40% ($40) | $60.00 | $12.00 | $48.00 | 52.0% (not 60%) |
| $100.00 | 50% ($50) | $50.00 | $10.00 | $40.00 | 60.0% (not 70%) |
- For 10% off: Move the decimal point one place left ($60 → $6.00 savings).
- For 20% off: Find 10% and double it ($6.00 × 2 = $12.00 savings).
- For 15% off: Find 10% and add half of that ($6.00 + $3.00 = $9.00 savings).
- For 25% off: Cut the price in half twice ($60 → $30 → $15.00 savings).
Common Discount Equivalents (Cheat Sheet for $100 Item)
| Discount Rate | Multiplier | You Save ($100 Item) | You Pay ($100 Item) |
|---|---|---|---|
| 10% Off | × 0.90 | $10.00 | $90.00 |
| 20% Off | × 0.80 | $20.00 | $80.00 |
| 25% Off (1/4 off) | × 0.75 | $25.00 | $75.00 |
| 30% Off | × 0.70 | $30.00 | $70.00 |
| 33.3% Off (1/3 off) | × 0.667 | $33.33 | $66.67 |
| 40% Off | × 0.60 | $40.00 | $60.00 |
| 50% Off (Half Price) | × 0.50 | $50.00 | $50.00 |
| 60% Off | × 0.40 | $60.00 | $40.00 |
| 70% Off (Clearance) | × 0.30 | $70.00 | $30.00 |
| 75% Off (3/4 off) | × 0.25 | $75.00 | $25.00 |
Frequently Asked Questions
They are mathematically identical if both items have the exact same price. For two $20 shirts: BOGO 50% equals $20 + $10 = $30 total (25% off $40). However, if the items differ in price, stores apply the 50% discount to the cheaper item, resulting in less than a 25% total discount.
In almost all jurisdictions across the US, UK, Canada, and Australia, store discounts and manufacturer markdowns are taxed on the discounted sale price, not the original MSRP. However, in a few US states, manufacturer coupons (where the store is reimbursed by the brand) may be taxed on the full original value.
A markup is the percentage added to a wholesale cost to set the retail selling price (e.g. $50 cost + 100% markup = $100 price). A discount is the percentage deducted from the retail price to reach a sale price. Note that a 50% markup followed by a 50% discount results in a loss ($100 → +50% = $150 → −50% = $75).
Divide the sale price by (1 − (Discount % ÷ 100)). For example, if you paid $60 on a 25% off sale: $60 ÷ (1 − 0.25) = $60 ÷ 0.75 = $80.00 original price.