Discount 1
Price after—
True Discount Calculator
See the true discount from stacked promotions. Enter price and percentages to track the price after each step.
Discount 2
Price after—
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The math uses only the numbers you enter. Store tags may round or include fees.
Why calculate the true discount?
Stores often stack promotions or highlight percentages that look bigger than what you actually save. The true discount shows what you really pay and keep in your pocket, without mistaking 30% + 20% for 50%.
When to use this calculator
Use it for online sales, outlets, grocery deals, or any tag with more than one discount or a was/now price. It helps compare offers before you buy. It does not include shipping, fees, cashback, or coupons applied after checkout.
How to read the result
Three numbers summarize the deal:
- Price after each discount: the chain shows how the value drops at every step.
- Summary bar: true total discount, final price, and savings in money.
- Educational note: a reminder that stacked percentages do not add in your head.
What stacked discount means
When two discounts apply in sequence, each one hits the already reduced price, not the full list price. That is why 30% then 20% equals 44% true discount, not 50%.
Formula
We multiply each discount factor and compare to the original price:
Pf = Po × (1 − d1/100) × (1 − d2/100) × …
Dr = (1 − Pf/Po) × 100
- Po
- Original (list) price.
- Pf
- Final (sale) price after all discounts.
- Dr
- True total discount in percent.
- di
- Each percentage discount applied in order.
Example
A $100 item with 30% off becomes $70. Another 20% on $70 is $56. The true discount is 44%, not 50%. You save $44.
Why it helps day to day
Comparing deals is fairer when you see the real percent. It helps you decide whether to wait, switch stores, or take the sale price.
Practical tips
- Adding percentages in your head is only a rough guess. Use the true discount to compare offers.
- In list/sale mode, check that the was price is a real reference, not an inflated anchor.
- Shipping, card interest, and fees come later. This tool handles item price only.
- To split a purchase among friends, use the group expense split calculator on this site.
Limitations
It does not simulate store rules (max discount, per-item rounding, buy 3 pay 2). It is not a receipt. Use it as a reference before you check out.
Knowing the true discount avoids checkout surprises and makes price comparisons more honest.
Compound multiplicative discount is standard retail and personal finance arithmetic.
Frequently asked questions
Can I add the percentages?
Not for the true discount. Each percent applies to the already reduced price. Add them only if you want a quick, imprecise estimate.
Does discount order matter?
When all are percentages on the running price, order does not change the final result. What matters is applying them one after another, not adding.
What if I only know list and sale price?
Use list/sale mode. Enter both values and the calculator shows true discount and savings.
How do I compare two deals?
Calculate the true discount for each with the same original reference, or compare final prices directly if the product is identical.