Discount Calculator
Calculate sale price and savings from original price and discount percentage. Compare stacked discounts (20% off + extra 10%), bundle deals and Black Friday math.
Last updated: May 2026
Enter price and discount to see the sale price.
Sale math and percentage discounts
Percentage discounts are applied as a simple multiplier: a 25% discount means you pay 75% of the original price. The formula is final price = original × (1 - discount ÷ 100). A €100 item with 25% off = €100 × 0.75 = €75. Many people struggle with percentage math, which is why this calculator is useful when comparing sales across different price points.
Discounts stack multiply, not add. A shirt with 20% off, then 10% off the discounted price, is not 30% off the original. It's 20% off, then 10% off that result, which equals about 28% total. Always apply discounts sequentially if you're stacking them, or just multiply the multipliers: 0.8 × 0.9 = 0.72 (28% off).
Frequently Asked Questions
How is the sale price calculated?
The sale price equals the original price multiplied by (1 minus the discount percentage divided by 100). For example, a 20% discount on €50 gives €50 × 0.8 = €40.
Can I calculate the discount percentage from two prices?
Yes. Divide the difference by the original price and multiply by 100: (original - sale) ÷ original × 100. For example, if €100 becomes €75, the discount is (25 ÷ 100) × 100 = 25%.
How do stacked discounts work?
Stacked discounts multiply, not add. A 20% discount followed by 10% off the discounted price equals 0.8 × 0.9 = 0.72 remaining (28% total discount), not 30% off. Always multiply the decimal multipliers together.