Amazon gives you the numbers.
This tells you which of them is a problem.

Breakeven ACOS, per product

Price, less landed cost, Amazon’s referral fee, fulfilment and anything else variable, as a share of the price. That share is the ceiling: spend more than it advertising a unit and the unit loses money. Every bid in the product is derived from this one number.

A product below zero is flagged loudly. It loses money on every sale before a penny of advertising, and no bid change fixes that.

Where each figure came from

The price you were actually paid, fees from your Fee Preview, landed cost from your own sheet. Each figure is labelled exact, derived or estimated, so you know which numbers to lean on and which to go and check.

Fees are category-correct across all 34 Amazon categories, including the tiered ones that stack rates across bands rather than applying one rate.

A profit and loss that includes your own costs

Storage, a VA, software, freight outside Amazon. None of it appears in any Amazon report, and without it a net profit figure flatters you. A line we were not given is never treated as a zero.

A forecast that admits what it is

Trailing trend and day-of-week shape, shown as a range built from your own week-to-week spread, never a single number. Under eight weeks of data it says the forecast is unreliable and shows it anyway, with that warning attached.

One formula, applied everywhere

ACOS is cost per click divided by conversion rate times order value. Rearranged, the most a click can be worth is your target ACOS times conversion times order value. That is the whole of it, and every recommendation shows its working.

Guardrails that do not get tired

No bid derived from under ten clicks. No single move larger than 15%. Never a bid change and a placement change on the same campaign in the same week, because then you cannot tell which one worked.

Thirteen of these rules are yours to set from Settings, each with limits that cannot be crossed and the reason printed beside it.

It knows Amazon charges more than your bid

Dynamic bidding and placement adjustments can take a click well above what you set. The gap between your bid and what you were actually charged is measured per keyword and built into the number it gives you back.

Sponsored Products, Brands and Display

All three read from one upload. A Brands campaign on a lifetime budget is not paced day by day, and a Display campaign charged per thousand views is not given a cost-per-click bid. Both are refused out loud rather than answered with a made-up number.

Harvest, with the other half attached

A term that has proven itself is promoted to exact at a bid derived from its own conversion rate, and negated in the campaign it came from, in the same file. Promote without negating and your two campaigns bid against each other.

It can also build the whole campaign for a harvested term: campaign, ad group, product ad and keyword, ready to upload.

Negation on clicks, never on ACOS

A term is negated when it has taken at least twice the clicks that product normally needs for a sale and made none. A term that converts but costs too much is never negated; it gets its bid cut. Negation throws a real buying signal away for good; a bid cut just reprices it.

The losing word, not just the losing term

Fifty terms wasting three dollars each look like noise one at a time. Split into their component words and rolled up, they usually share a root: free, cheap, a competitor’s name. One negative phrase does the work of fifty negative exacts.

Where you are bidding against yourself

The same keyword live in two campaigns means Amazon enters one of them and you push your own price up, while the evidence splits in two. It names the copy that converts best and what to do with the others. Never “delete”, because that throws the history away.

Budget pacing that refuses to guess

Spend and days come from the same dated file. With no dates it says so rather than dividing by a number it invented, and it will not report a utilisation Amazon’s monthly averaging makes impossible.

Share of search

Brand Analytics is the only free Amazon report that says where you stand against everyone else selling into the same search. It is what lets a launch be judged on rank moving rather than on an ACOS it was never meant to hit.

An event plan for Prime Day

Warm-up, event and cool-down budgets per campaign, derived from breakeven. Scale campaigns are raised only where they are already inside target, launches get a ceiling and a stop condition, and harvest campaigns are held. Terms “proven” during an event are proven against a week that will not happen again for a year.

Ninety days, then eighteen months

Amazon keeps about ninety days of search term history, and only sixty on Sponsored Brands and Display, then deletes the rest. Upload weekly, or connect your Amazon Advertising account when the connection ships, and you hold eighteen months, the longest Amazon’s own rules allow anyone to keep it. It is yours: never sold, never shared, never pooled with anybody else’s. A day already held is written once, so nothing ever doubles.

Three reasons, each given its share

ACOS can only rise for three reasons: clicks got dearer, fewer of them converted, or orders got smaller. The movement is split between the three and each given its share, per product and per campaign, not just across the account, where the answer is usually “a mix”.

A conversion problem is never answered with a bid

If conversion fell while the cost per click held, the problem is your listing and a bid cut makes it worse. That distinction is the whole reason the decomposition exists.