BREAK-EVEN ACOS CALCULATOR

BREAK-EVEN ACOS Calculator

See the ACoS above which an advertised sale stops making money, including the 16.67 points VAT registration takes off it, with a free calculator and Excel workbook.

Free tool

Break-Even ACoS Calculator

Break-even ACoS is the advertising cost of sale above which a unit stops making money, however healthy the campaign looks in Seller Central. It is not your gross margin, and on a VAT-registered account it is roughly half what most sellers assume.

£
The price the buyer pays, including VAT. This is the figure Amazon reports as sales, so it is the one ACoS is measured against.
%
20 if you are registered, 0 if you are not. Amazon charges its fee on the full price either way.
£
Unit cost plus freight, duty, clearance and handling. Not the supplier invoice on its own.
%
Most categories are 15. Charged on the full price the buyer paid, with a 25p minimum.
£
The per-unit fulfilment fee for your size tier. Enter your own pick and pack cost if you fulfil it yourself.
%
Charged on your Amazon fees, not on the sale. Small, easy to forget, and it is on every order.
£
Prep, labelling, inbound shipping to the fulfilment centre, and any allowance for returns.
%
Optional. What your campaigns are actually running at, so the tool can tell you what that is worth.
%
Optional. Sessions that turn into orders, used to work out the most you can pay for a click.
Break-even ACoS

Fill in a selling price to see the answer.

Net revenue after VAT

Amazon takes

Contribution before advertising


Break-even ROAS, the same number inverted

Most you can pay for a click


Advertising at your actual ACoS

Profit per unit after advertising

Break-even ACoS is simply your contribution as a percentage of the selling price. Nothing else. Comparing an ACoS to your gross margin instead is the mistake that funds a lot of unprofitable advertising.

Free download

Take this calculator into Excel

The workbook version runs the same numbers for up to ten ASINs side by side and ranks them by the gap between the ACoS you are running and the ACoS you can afford. A blended target that is right on average is usually wrong on every individual product.

Download the Excel workbook XLSX · free · no signup required Not sure what your true landed cost or margin is? Get in touch

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