Free Amazon ACoS calculator

Calculate the ACoS ceiling your unit economics actually support.

Enter your own selling price and costs. CEILR calculates pre-ad contribution, allowable ad spend per order and the corresponding ACoS ceiling. Protect a contribution target if you want a stricter-than-break-even result.

Transparent formula

No hidden demand estimate. No Amazon login required.

This calculator runs in your browser and uses only the values you enter.

1ContributionPrice minus represented costs
2Ad roomContribution minus protected amount
3ACoS ceilingAd room ÷ selling price
Show the working

Pre-ad contribution = selling price − landed cost − Amazon/per-order fees − other per-order costs.

Allowable ad spend/order = max(0, pre-ad contribution − protected contribution/order).

ACoS ceiling = allowable ad spend/order ÷ selling price.

Optional CPC ceiling = allowable ad spend/order × conversion rate.

If protected contribution is zero, the ACoS result is a simple break-even advertising ceiling based on the represented order-level costs. Add a protected amount to model a stricter target.

YOUR INPUTS

Amazon advertising ceiling

Pre-ad contributionBefore advertising
Allowable ad spend / orderAfter protected contribution
ACoS ceilingModeled spend ratio
Optional CPC ceilingOptional CVRUses entered conversion rate

Enter selling price, landed cost and Amazon/per-order fees.

What this calculator does not know

Your ACoS target is only as complete as the costs you represent.

Returns, refunds, storage, promotions, taxes, overhead, financing, marketplace-specific costs and other expenses can change real profitability. The calculator does not retrieve or estimate them.

Educational decision-support only. It does not guarantee profit, sales, conversion, advertising performance or Amazon ranking. See the full CEILR methodology.

Connect the ceiling

ACoS is more useful when cash and inventory are in the same decision.