Stacked Discount Calculator

Find the real percentage off when two or three discounts stack, applied one after another or all from the original price.

Your numbers

▾

Price

Original price

Your cost (optional)

Add it to see the margin left after both discounts.

Discounts, in the order they apply

First discount

First discount value

For example an automatic sale on the product.

Second discount

Second discount value

For example a discount code at checkout.

Add a third discount

How they stack

Stacking method

Your result · updates as you type

Real discount

32.5% off

25% off + 10% off on $80.00 leaves $54.00. Not the 35% it sounds like.

Final price: $54.00
Customer saves: $26.00
If all came off the original: $52.00 (35% off)

Two percentage discounts applied one after another multiply: 1 − (1 − a) × (1 − b). Taken from the same original price, they add up, which costs you more.

Final price

Original

$80.00

One after another

$54.00

All from original

$52.00

Breakdown

Original price: $80.00
First: 25% off: −$20.00 → $60.00
Second: 10% off: −$6.00 → $54.00
Final price: $54.00

Why 25% + 10% isn't 35%

When the second discount is taken from the already-reduced price, it's worth less than it sounds. Percentages multiply instead of adding.

Real discount = 1 − (1 − first) × (1 − second)

Example: the default numbers

Original price: $80.00
25% sale: −$20.00 → $60.00
10% code, on the sale price: −$6.00 → $54.00

The customer pays $54.00, a real discount of 32.5%. Taken from the original price instead, both would add up to 35% and the price would be $52.00.

How Shopify and WooCommerce stack discounts

Situation	How it stacks
Shopify: product discount, then an order discount	One after another. The order discount applies to the subtotal after product discounts.
Shopify: two or more order discounts	Percentages all come off the same subtotal, then fixed amounts.
Shopify Plus: two product discounts on one item (tagged to stack)	Percentages from the original price first, then fixed amounts.
WooCommerce: several coupons (default)	Based on the original product prices.
WooCommerce: “Calculate coupon discounts sequentially” on	One after another, each on top of the last.

In Shopify, discounts only combine when each is set to combine with the other's class under Combinations on the discount. In WooCommerce, the sequential option is under WooCommerce → Settings → General, in the coupon settings.

Protecting your margin

Add your cost. The calculator then shows the margin left after every discount, and warns if you sell below cost.
Stop codes stacking on sales. In Shopify, leave the code's combination setting off for product discounts during a sale.
Test the whole cart. Use the Shopify discount combination checker to see which discounts Shopify actually applies.

Questions people ask

How do you calculate a double discount?

Multiply what's left after each: 25% then 10% leaves 0.75 × 0.90 = 0.675 of the price, so the real discount is 32.5%.

Is 20% off plus 20% off the same as 40% off?

Only if both are taken from the original price. One after another, it's 36% off: 0.8 × 0.8 = 0.64.

Can customers use two discount codes on Shopify?

Yes, if both codes are set to combine with each other's class. Shopify allows up to 5 product or order discount codes and 1 shipping code per order.

Does WooCommerce apply coupons one after another?

Not by default: coupons are based on the original product prices. Turn on Calculate coupon discounts sequentially in the general settings to apply them in sequence.

Last reviewed 30 September 2026.

Sources: Shopify Help Center: Combining discounts · Shopify Changelog: Multiple product discounts on the same item · WooCommerce docs: General settings (coupon calculation) · WooCommerce docs: Coupon management