ACoS & Break-Even Ad Calculator
“My ACoS is 25% — is that good?” has no answer on its own; it depends on your margin. This tool finds your break-even ACoS first, then compares your actual performance against it.
Currency doesn't matter — keep every field in the same one. Unit cost must EXCLUDE ads; we handle those separately.
Break-even ACoS
38.3%
Above this, every advertised sale loses money. Your current ACoS is 28.1%.
This period's ad result
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How it's calculated
Break-even ACoS = (price − unit cost excluding ads) ÷ price. It's the share of price left before advertising. The moment your ad cost passes it, that sale makes revenue but destroys profit.
ACoS = ad spend ÷ ad-attributed sales. ROAS is its inverse (1 ÷ ACoS) — the same information, reported differently by different platforms. The tool shows both.
TACoS = ad spend ÷ total sales (including organic). ACoS measures the ads; TACoS measures how dependent the business is on them. A falling TACoS means organic sales are growing.
Finally it computes the net contribution of ads: gross margin on ad-driven sales minus ad spend. If that's negative, the ads lost money regardless of the ACoS figure.
What people most often forget
- Put everything into unit cost: product, freight, marketplace fee, fulfilment and a returns allowance. Anything left out inflates your break-even ACoS and disguises a loss as a profit.
- Exceeding break-even during a launch is a deliberate investment in rank and first reviews. The problem is when it quietly becomes permanent.
- The organic halo doesn't show up in ACoS. Ad sales lift rank, rank brings organic sales. Cutting budget on ACoS alone often shrinks total revenue — read TACoS alongside it.
- Look per campaign. A blended ACoS averages very profitable and very wasteful campaigns together; the average can look fine while a third of the budget is wasted.
- A new product and a mature one can't share a target. Mature products optimise for profit; new ones buy data and rank.
Scope, sources and freshness
The tool is platform-agnostic: the same logic applies to Amazon, Etsy, Trendyol or Google/Meta ads. Keep every field in one currency. The “ad-attributed sales” figure comes from the platform's own attribution model, which is generally generous and varies by platform. For true profit, trust your accounts rather than the ad report.
Sources last reviewed: 14 August 2026
Frequently asked
What's a good ACoS?
There is no universal number. A good ACoS is any figure below your own break-even ACoS. At 40% margin, 30% ACoS is profitable; at 20% margin the same figure loses money.
What's the difference between ACoS and ROAS?
Two views of the same number. ACoS = spend ÷ sales (lower is better); ROAS = sales ÷ spend (higher is better). 25% ACoS equals 4× ROAS.
Why can TACoS matter more than ACoS?
It shows dependence on ads. If ACoS holds steady while TACoS falls, organic sales are growing; a rising TACoS means growth is being bought entirely with spend.
Should I switch off unprofitable ads immediately?
If the product is new, no — running above break-even for a while buys first sales, reviews and rank. If it's mature and has been losing for months, yes, but check the campaign breakdown first: usually a small slice of budget produces most of the loss.
Why include a returns allowance in unit cost?
Returns don't refund the fulfilment cost and often can't be resold. Leaving them out overstates your break-even ACoS.
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