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Discount Calculator

Calculate the final sale price, amount saved, and percentage off for any discount. Or find the original price from a sale price. Handles single and stacked discounts. Free, no signup.

Calculate Discount
Quick discount:
$
YOU SAVE
$20.00
20% off
SALE PRICE
$80.00
final price
$
ORIGINAL PRICE WAS
$80.00
You saved $20.00
$
Original Price—
After 1st discount—
After 2nd discount—
Total saved—
Effective discount—

How Discounts Are Calculated

Understanding discount math protects you from misleading sale signs and helps you quickly evaluate whether a deal is actually good.

Sale Price = Original × (1 − Discount/100) Amount Saved = Original × (Discount/100) Original Price = Sale Price / (1 − Discount/100)

The stacked discount trap

Retailers often advertise "20% off, plus extra 10% off." Many shoppers assume this is 30% off. It is not — it's 28% off. Here's why: the second discount applies to the already-reduced price, not the original. A $200 item with 20% off = $160. Then 10% off $160 = $144 — not $140 as 30% off would give. Use the stacked discount tab above to check any combination.

Recognizing fake discounts

The FTC requires that advertised "original prices" must be prices at which the item was genuinely offered for sale for a reasonable period. Watch for: items with permanently inflated "compare at" prices, sale prices that are actually the regular price, and "limited time" sales that never end. Compare prices across retailers and use tools like CamelCamelCamel for Amazon price history before assuming a sale is real.

Frequently Asked Questions

What is 30% off $50?
30% off $50 = $50 × 0.30 = $15 discount → $35 final price. Quick check: 10% of $50 = $5, so 30% = $15 off, leaving $35.
Is 20% off + 10% off the same as 30% off?
No. 20% off + 10% off = 28% off total. The second discount applies to the already-reduced price. On a $100 item: 20% off = $80, then 10% off $80 = $72. True 30% off would give $70. You're paying $2 more with stacked discounts.
How do I calculate original price from a sale price?
Divide the sale price by (1 − discount rate). Example: paid $75 after 25% off → $75 / (1 − 0.25) = $75 / 0.75 = $100 original price. This formula is useful when you only see the sale tag and want to verify the claimed discount.