Discount Calculator
Calculate discount, tax, and final checkout price.
What is a Discount?
A discount is a reduction in the original price of a product or service. Discounts can be expressed as a percentage (25% off) or a fixed amount ($20 off). Understanding how to calculate discounts helps you compare deals, verify sale prices, and make informed purchasing decisions.
Discount Calculation Formula
Discount Amount = Original Price * (Discount Percentage / 100). Sale Price = Original Price - Discount Amount. For example, a $200 item at 30% off: Discount = $200 * 0.30 = $60. Sale Price = $200 - $60 = $140. You save $60.
How Stacked Discounts Work
When multiple discounts apply, they're calculated sequentially, not added. Example: $100 item with 20% + 10% off. First: $100 - 20% = $80. Then: $80 - 10% = $72. Total savings: $28 (28% effective discount), not $30 (30%). Always calculate each discount on the reduced price.
Comparing Deals
To compare different discount offers: calculate the final sale price for each. $50 item: 25% off = $37.50. $50 item: $10 off = $40. The percentage discount is better. For different original prices: Item A $100 at 20% off = $80. Item B $90 at 15% off = $76.50. Item B is cheaper despite the lower percentage.
Discount Shopping Tips
Calculate the final price, not just the discount amount. Be wary of inflated original prices (check price history). Compare unit prices for different sizes. Stacked discounts aren't additive—calculate sequentially. Check if the 'sale' price is actually the regular price elsewhere. Consider if you need the item, not just if it's on sale.
Comparison Analysis
Single vs Stacked Discounts ($100 Item)
| Criteria | 30% Off | 20% + 10% Off | 25% + 5% Off | $30 Off |
|---|---|---|---|---|
| Final Price | $70 | $72 | $71.25 | $70 |
| Total Savings | $30 | $28 | $28.75 | $30 |
| Effective Rate | 30% | 28% | 28.75% | 30% |
| Best Deal | Yes (tied) | No | No | Yes (tied) |
Content Verification
Expert Review
Reviewed by Susan Clark, Consumer Finance Advocate, Retail Pricing Analyst
Authoritative Sources
Based on FTC consumer protection guidelines, Consumer Reports research, and retail industry standards
Last Reviewed
Content verified May 2026 against current retail pricing practices and consumer protection standards