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Calculate sale price after discount. Use for percent off; for change percent use percentage-change-calculator. Input: price + percent. Returns final price. 100% client-side, files never leave browser.
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Applies one or more discount percentages in sequence to a starting price and shows the final price, the total amount saved, and the effective discount percentage. Discounts stack multiplicatively: a 20% off + 10% off stack is 28% off, not 30%.
Most shoppers intuitively add discount percentages, but stores always apply them in sequence. A 20% + 10% coupon is 1 − 0.8 × 0.7 = 0.44, so 44% off, not 30%. This calculator shows the real final price for any stack of discounts, the actual dollar amount saved, and the effective percentage so you can compare to 'X% off' offers.
This tool is part of the DevStackIO platform — a collection of free online developer tools from DevStackIO. Browse more free developer resources on DevStackIO.
Shoppers comparing stacked coupon offers, retail marketers designing promotion campaigns, e-commerce analysts evaluating discount effectiveness, and small business owners sanity-checking sale pricing.
Enter the original price (the pre-discount price)
Enter the discount percentages in the order they'll be applied, separated by commas or newlines
Read the final price, the amount saved, and the effective percentage
The step-by-step breakdown shows each discount and the running subtotal
Edit the input to recompute instantly
$100 with 20% off → $80 (saves $20, 20% effective)$100 with 20% + 10% off → $72 (saves $28, 28% effective)$200 with 30% + 10% + 5% off → $119.70 (saves $80.30, 40.15% effective)$50 with 50% off → $25 (saves $25, 50% effective)$100 with 20% off + 20% off → $64 (saves $36, 36% effective)How does stacking work?
Each discount multiplies the running subtotal. A 20% discount on $100 leaves $80; a 10% discount on that leaves $80 × 0.9 = $72. The final is 1 − (0.8 × 0.9) = 1 − 0.72 = 0.28 of the original, so 28% off.
Why is 20% + 10% = 28% and not 30%?
Because each discount is taken on the running total, not the original. $100 × 0.8 × 0.9 = $72, which is 28% off the original. Adding the percentages would only work if the discounts applied to non-overlapping portions of the price.
Does the order of discounts matter?
Mathematically no: multiplication is commutative. In practice, stores always apply the larger discount first, so the line items differ. The final price is the same either way.
What about 'BOGO free' (buy one get one free)?
That depends on the relative price of the two items. The simplest case (BOGO where the second item is the same price) is 50% off if you buy 2. For mixed carts, treat each line as its own discount calculation.
Is this calculator accurate?
Yes, uses standard arithmetic with full floating-point precision. The displayed values are rounded for readability; the final price is exact to 2 decimal places.
Authoritative specifications, standards, and in-depth reading for Discount Calculator.
Final price
$80.00
You save
$20.00
Effective
20% off
Stacked discounts multiply, not add. A 20% + 10% stack is 28% off, not 30%.
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