π·οΈ Discount Calculator
Sale prices, stacked discounts, savings, and reverse price lookup.
Sale Price
How to Use This Calculator
Enter the original price and the discount percentage to see the sale price and your total savings. Add a second discount for stacked coupons, and sales tax to see the checkout total. Switch to reverse mode to work backwards from a sale price.
Choose "Find sale price" or "Find original price".
Enter the price and the discount percentage. Add a second discount if you are stacking coupons.
Optionally add sales tax to see what you actually pay at checkout.
Read the effective discount: with stacked coupons this is the number stores hope you will not compute.
The Stacked Discount Math
Discounts multiply, they do not add. A 20 percent coupon stacked with 10 percent off gives an effective discount of 28 percent, because the second coupon applies to the already-discounted price. The general rule: convert each discount to its "keep" multiplier (20 percent off = keep 0.80), multiply them, and subtract from 1. Three stacked discounts of 20, 10, and 5 percent give 1 - (0.80 x 0.90 x 0.95) = 31.6 percent off. This is why "extra 10 percent off sale items" is worth less than it sounds.
Worked Example
Jacket listed at $120, store sale 25 percent off, plus a 10 percent coupon, 8 percent sales tax. After the store discount: 120 x 0.75 = $90. After the coupon: 90 x 0.90 = $81. With tax: 81 x 1.08 = $87.48 at checkout. Total savings versus list: 120 - 81 = $39, an effective discount of 32.5 percent. Working backwards: if you only knew the $81 sale price and the stacked 32.5 percent effective discount, the original was 81 / (1 - 0.325) = $120.
Discount Psychology to Watch For
Retailers use a few reliable tricks. The inflated "was" price makes a modest cut look dramatic, which is why comparing against other stores matters more than the stated percent off. "Up to 50 percent off" usually means one item is half price and the rest are 10 percent off. And buy-one-get-one-half-off is just 25 percent off two items, not 50 percent off. Running the numbers yourself, which takes ten seconds here, is the simplest defense.
Frequently Asked Questions
How do stacked discounts work?
Stacked discounts apply one after another, not added together. A 20 percent discount followed by 10 percent off means you pay 80 percent, then 90 percent of that: 0.80 x 0.90 = 0.72, so 28 percent off total, not 30 percent. Stores love advertising stacked discounts because the combined number sounds bigger than it is.
Why is 20% off plus 10% off not 30% off?
Because the second discount applies to the already-reduced price. On $100: 20 percent off leaves $80, then 10 percent off $80 saves $8 more, for $72 total. That is $28 saved (28 percent), not $30. The bigger the first discount, the more the second one shrinks in dollar terms.
How do I find the original price from a sale price?
Divide the sale price by (1 minus the discount as a decimal). If something costs $72 after 20 percent off, the original price was 72 / 0.80 = $90. Use the reverse mode in this calculator and it does the division for you.
Should I use a percent-off coupon or a fixed-dollar coupon?
It depends on the price. A $10-off coupon beats 10 percent off on anything under $100, while 10 percent off wins above $100. At exactly $100 they tie. This calculator shows both so you can compare before you check out.
What is a good discount?
For everyday retail, 20 to 30 percent off is a solid sale; 40 to 50 percent usually means clearance or end-of-season stock. Anything above 60 percent off deserves a look at the original price, since some stores inflate the "was" price to make the discount look bigger.