Amazon PPC and profit terms, defined with their arithmetic.

The highest cost per click that still leaves the seller the contribution per order they said they need to keep. It is derived from the seller's own entered economics, not from a category benchmark or an estimate.

Formula(pre-ad contribution − protected contribution) × conversion rate

The highest cost per click the seller's available advertising cash can actually fund across the click volume they plan to buy. A keyword can be economically profitable and still be unfundable this month.

Formulaavailable advertising cash ÷ planned clicks

The lower of Profit-Safe CPC and Fundable CPC. Profitability and cash are separate constraints, and the binding one is whichever is smaller.

Formulamin(Profit-Safe CPC, Fundable CPC)

Whether the data supporting a decision is current, stale or absent. CEILR marks missing evidence as missing rather than substituting an estimate, so a decision is never presented as better supported than it is.

The retained reasoning, inputs and evidence behind a decision the seller previously made, so a later change can be judged against what was actually known at the time.

Advertising spend on a search term with no orders, where the accumulated loss has reached or passed the seller's stated maximum acceptable test loss. It is a conclusion drawn from evidence, not a spend threshold.

A search term whose spend is producing genuine contribution after all fees and costs, making it a candidate for more deliberate investment.

A search term that produces orders while losing money after fees, landed cost and ad spend. It is neither waste nor a harvest candidate, and CEILR counts it separately rather than forcing it into one of those two.

The advertising cost of sale at which an order contributes exactly nothing. Above it every additional order loses money.

Formulapre-ad contribution ÷ net selling price

The cost per click at which advertising exactly consumes the contribution the resulting orders produce.

Formulapre-ad contribution × conversion rate

The advertising cost of sale that leaves the seller their protected contribution per order intact.

Formula(pre-ad contribution − protected contribution) ÷ net selling price

Advertising cost of sale: advertising spend as a proportion of the sales that advertising produced. It says nothing about profit on its own, because it ignores landed cost and fees.

Formulaad spend ÷ ad sales

Total advertising cost of sale: advertising spend against total sales, organic included. It tracks whether advertising dependence is rising or falling over time.

Formulaad spend ÷ total sales

Return on ad spend, the reciprocal of ACoS. Like ACoS it is a revenue ratio, not a profit measure.

Formulaad sales ÷ ad spend

The share of clicks that become orders. It converts a per-order contribution figure into a per-click ceiling, which is why an unreliable conversion rate makes every CPC ceiling unreliable.

Formulaorders ÷ clicks

What one order contributes before any advertising cost: the net selling price less landed cost, referral fee, fulfilment fee and other variable costs. Every advertising ceiling on this page is derived from it.

Formulanet selling price − landed cost − referral fee − fulfilment fee − other variable cost

The selling price excluding recoverable consumption tax. For a GST-registered Australian seller on a GST-inclusive price, this is the listed price divided by 1.1.

Formulalisted price ÷ (1 + tax rate), where the price includes recoverable tax

The contribution per order the seller has decided to keep rather than spend on advertising. It is an input the seller states, not a figure CEILR infers.

The total loss a seller is willing to absorb while testing a search term before treating the result as evidence rather than noise.

The full cost of getting one unit into Amazon's network: goods, freight, duty and inbound handling. Excluding any part of it inflates every downstream ceiling.

Amazon's commission on the sale, charged as a percentage of the selling price and varying by category.

Formulanet selling price × referral fee rate

How long current sellable inventory lasts at the current rate of sale. It bounds how much demand it is rational to buy with advertising.

Formulaunits on hand ÷ average daily units sold

The inventory level at which a replenishment order must be placed to avoid a stockout, given supplier and inbound lead time.

Formula(average daily units sold × lead time in days) + safety stock

The buffer held against demand and lead-time variability, above what average sales alone would require.