Discount Calculator

Standard Discount Formula

The core formula to find the sale price: Sale Price = Original Price × (1 − Discount% ÷ 100)

$80 item at 25% off → $80 × 0.75 = $60
Savings = Original − Sale Price → $80 − $60 = $20
Savings % = (Savings ÷ Original) × 100 → 25%

Stacked / Multiple Discounts

When two discounts apply in sequence, each one reduces the already-discounted price — they do not simply add up:

$100 at 20% off → $80, then 10% off → $80 × 0.90 = $72
Combined saving = $28 = 28%, not 30%
Formula: Final = Original × (1 − D1÷100) × (1 − D2÷100)

Reverse Discount Formulas

Two common reverse problems solved:

• Find original price: Original = Sale Price ÷ (1 − Discount% ÷ 100). Paid $60 after 25% off → $60 ÷ 0.75 = $80
• Find discount %: Discount% = ((Original − Sale) ÷ Original) × 100. $80 → $60 → ((80−60)÷80)×100 = 25%

Discount with Sales Tax

Tax is applied after the discount in most jurisdictions: Total = Sale Price × (1 + Tax% ÷ 100)

💡 Pro Tips for Discount Calculations

• Two 50% discounts ≠ 100% off. Stacked discounts compound — 50% then 50% leaves you paying 25% of the original price.
• Use the Reverse mode when a price tag shows only the sale price — enter the sale price and the discount % to recover the original retail price.
• Compare mode is ideal for Black Friday shopping — enter two stores' prices and discounts to find the better deal in one click.
• Tax timing matters: in most US states, sales tax applies to the discounted price, not the original — always calculate discount first, then tax.