Pick what you know, then fill in two numbers.
The price before any discount is applied.
The percent off advertised, for example 20 for 20% off.
Stacked discounts do not add up. Two 20% discounts are not 40% off, they are 36% off, because the second one applies to the already reduced price. A $129 item drops to $103.20, then to $82.56, a total saving of $46.44.
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Multiply the original price by the discount percentage, then divide by 100 to get the amount saved. Subtract that saving from the original price to get what you pay. A quicker version is to multiply the price by (100 minus the discount) divided by 100, which gives the final price in one step.
20% of $129 is $25.80, so the final price is $103.20. Working it through: $129 times 20 divided by 100 gives $25.80 of savings, and $129 minus $25.80 leaves $103.20. The one-step version is $129 times 0.80, which lands on the same $103.20.
25% off $80 saves you $20 and leaves a final price of $60. A quarter off is one of the easiest discounts to do in your head, because you only need to divide the price by four and subtract the result.
15% of $60 is $9, so you pay $51. Split it into two easy parts: 10% of $60 is $6, half of that is $3 for the extra 5%, and $6 plus $3 gives the $9 saving.
Divide the sale price by (100 minus the discount percentage) divided by 100. If an item is $51 after 15% off, divide $51 by 0.85 to get the original price of $60. Do not add 15% back to $51, because that gives $58.65 and understates the real starting price.
Subtract the sale price from the original price, divide the result by the original price, then multiply by 100. A $129 item now selling for $103.20 has a saving of $25.80, and $25.80 divided by $129 is 0.2, which is 20% off. Use the third mode above to do it automatically.
Because the second discount applies to the already reduced price, not the original one. A $129 item at 20% off becomes $103.20, and another 20% off that is $82.56, so you have saved $46.44 in total, which is 36% off. Stacked percentages multiply rather than add, and the gap widens the deeper the discounts get.
Start with 10%, which is just the price with the decimal point moved one place left. For 20% off $129, take $12.90 and double it to get $25.80. Build any other figure from the same blocks: halve the 10% for 5%, and add the pieces together.
After. Tax is charged on what you actually pay, so the discount comes off first and the tax is calculated on the reduced amount. On a $129 item at 20% off, tax applies to $103.20, so at an 8% rate you pay $8.26 of tax and $111.46 in total.
Far more than the headline percentage suggests, because the discount comes out of profit rather than revenue. An item that costs $60 and sells for $100 carries a 40% margin and $40 of profit. Discount it by 20% and the price is $80, so the profit is $20, meaning a fifth off the price removed half the profit.
A percent off scales with the price, so 20% off saves more on expensive items than on cheap ones. An amount off is a fixed sum, so $20 off is 20% on a $100 order and 40% on a $50 order. Percentage discounts suit wide catalogues, while fixed amounts are easier for customers to judge on a single item.
Most retailers find 10% to 20% is enough to prompt a purchase without training customers to wait for a sale. Deeper cuts of 40% or more are best kept for clearing old stock, since they can wipe out the margin entirely on a normal product. Test the smallest discount that moves the needle before assuming a bigger one is needed.
Three come up again and again: adding stacked discounts together instead of applying them in sequence, adding a percentage back to a sale price to find the original, and applying tax before the discount. Each one produces a number that looks plausible but is wrong by a few percent, which matters once it is multiplied across a full order.
Yes. No signup, no email and no limit on how many discounts you run through it. It is built by Mage Loyalty, a loyalty, referrals and store credit app for Shopify.
Mage is a loyalty, referral and store credit app built for Shopify. Reward repeat purchases, run VIP tiers, and give customers a reason to come back, without writing a line of code.
