Discount Calculator (Sale Price)
What is the final price after a discount — including stacked coupons and sales tax?
Spec sheet
stacked_discount · v1.0.0Sequential (stacked) discounts, then tax
- 01
sale = price × (1 − d₁) × (1 − d₂) - 02
saved = price − sale - 03
total = sale × (1 + tax)
- Stacked discounts multiply; 20 % + 10 % is 28 %, not 30 %.
- Coupons with fixed-dollar amounts are not modeled.
- Percentage arithmeticformula
Worked example
computed by the same formula$80 at 25 % off, then 10 % extra
- Original price
- 80
- Discount
- 25 %
- Extra discount (applied after)
- 10 %
- Sales tax
- 0 %
- Sale price
- $54.00
- You save
- $26.00
- Effective discount
- 32.5 %
- Total with tax
- $54.00
Questions
How is the discount calculator calculated?
›
Sequential (stacked) discounts, then tax. sale = price × (1 − d₁) × (1 − d₂) · saved = price − sale · total = sale × (1 + tax)
Example: $80 at 25 % off, then 10 % extra?
›
Sale price: $54.00; you save: $26.00.
Is 20 % off plus 10 % off the same as 30 % off?
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No. The second discount applies to the already-reduced price, so the combined discount is 1 − 0.8 × 0.9 = 28 %.
What does this calculator not cover?
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Stacked discounts multiply; 20 % + 10 % is 28 %, not 30 %. Coupons with fixed-dollar amounts are not modeled.
Where do the numbers come from?
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Sources: Percentage arithmetic. The formula is versioned (stacked_discount v1.0.0) and covered by automated tests.
Is my data stored?
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No. The calculation runs in your browser and nothing is sent unless you choose to save a shareable link.
Also searched asdiscount calculator · sale price calculator · percent off calculator · 25 off 80 · price after discount · stacked discount