🏷️ Free Online Tool
Discount Calculator
Sale price, savings, stacked discounts and sales tax — calculated instantly. Plus a reverse mode that finds the original price from any sale tag. No signup, everything runs in your browser.
By UpnixTools · Calculator last reviewed October 2026
e.g. “20% off + extra 10% at checkout” — applied one after another.
You pay
$75.00
You save $25.00 (25%)
How discount math works
Sale price: original price − (original price × discount ÷ 100). A $100 jacket at 25% off costs $75 — you save $25.
Stacked discounts apply one after another. “30% off + extra 10%” on $100 → $70 after the first, then $63 after the second. Adding them (40% → $60) is the classic trap — stores count on you making it.
Reverse: original = sale price ÷ (1 − discount ÷ 100). That “$75 final” at 25% off was $100 before.
Discount Calculator FAQs
How do you calculate a discount?
Sale price = original price − (original price × discount ÷ 100). For example, a $100 item at 25% off: $100 − ($100 × 0.25) = $75. You save $25.
How do stacked discounts work (e.g. 20% + extra 10%)?
Stacked discounts apply one after another, not added together. A $100 item at 20% off becomes $80; an extra 10% off applies to $80, giving $72 — not $70. This calculator handles stacking automatically.
How do I find the original price from a sale price?
Use the reverse mode: original price = sale price ÷ (1 − discount ÷ 100). A $75 item at 25% off was originally $75 ÷ 0.75 = $100.
Is sales tax applied before or after the discount?
In most places tax is charged on the discounted (sale) price. This calculator applies tax after discounts, which matches how US state sales tax normally works.