ROAS is ad revenue divided by ad spend. ROAS 4.0 means $4 of sales per $1 of ads — the inverse of ACOS.
ROAS (Return on Ad Spend) is ad-attributed revenue divided by ad spend. A ROAS of 4.0 means every advertising dollar produced four dollars in sales.
Formula: ROAS = ad-attributed sales ÷ ad spend
ROAS and ACOS are two views of the same number: ROAS = 100 ÷ ACOS. ACOS 20% ⇔ ROAS 5.0; ACOS 50% ⇔ ROAS 2.0. Amazon-native sellers tend to think in ACOS; agencies coming from Google or Meta tend to think in ROAS.
What's a good ROAS on Amazon? Your break-even ROAS is 100 ÷ your margin percentage. With a 30% margin, ROAS 3.33 is break-even — anything above that is profitable ad spend. Convert between the two instantly with our free calculator.
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