ROAS Calculator

ROAS gets thrown around like it means something on its own. It doesn't. Revenue divided by ad spend gives you a multiple — spend $1,000, make $4,200, that's 4.2x ROAS. The number feels great. The problem is what it leaves out.

The first campaign I ever ran showed 5x ROAS and I thought I'd cracked it. Then I did the actual margin math and found I was up maybe a hundred bucks after fees. ROAS ignores your cost of goods, your referral fee, and your FBA fee. It only knows two numbers: what you put in and what the customer paid.

The 1x trap

A ROAS of 1x means you got your money back. That's it. You spent $1,000 and collected $1,000 in revenue. You did not profit. You covered the ad and then owe Amazon fees, your supplier, and shipping out of that same dollar. Anyone celebrating 1x ROAS is celebrating breaking even before expenses, which is a special kind of loss.

What ROAS you need to clear depends entirely on margin. A product keeping 25% after all costs needs ROAS above 4x just to stay flat. A thinner product needs more. There's no universal "good ROAS" — the number only means something next to your real margin.

ROAS vs ACOS

They're the same story told two ways. ROAS is revenue over spend; ACOS is spend over revenue. A 4x ROAS is a 25% ACOS. I use ACOS when talking to myself about margin headroom and ROAS when a dashboard forces it on me. Pick one and stay consistent so you're not comparing 4x to 20% and confusing yourself.

Use it honestly

Type your spend and your ad-attributed revenue. The tool gives the multiple. Then ask the harder question: after fees and COGS, did that multiple actually leave profit? If you don't know your margin, the ROAS number is a vanity metric. Run the Net Profit Calculator and the Break-Even ACOS tool, then come back. A 4.2x ROAS on a 25%-margin product is a win. On a 10%-margin product it's a slow bleed you'll notice only at the end of the month.