FBA STORAGE FEE ESTIMATOR

FBA STORAGE FEE Estimator

See what storage costs per unit sold rather than per month, and when your stock tips past the aged surcharge, with a free estimator and Excel workbook.

Free tool

FBA Storage Fee Estimator

What a cubic foot a month actually costs you per unit sold, which is a much larger number than the monthly rate. Enter your box in centimetres, because that is how you measure it and not how Amazon charges for it.

The box and the stock
cm
Packed, not the bare product.
cm
Amazon measures the unit as it sits on the shelf.
cm
A centimetre on each side matters more than you would think.
The shipment you have just sent in, or what is there now.
Your honest rate, not the good month.
£
What one sale leaves after goods, fees and fulfilment. Used to show storage as a share of it.
The rates, which you should check
£
Per cubic foot per month. Published UK figures vary between sources, so copy yours from Seller Central.
£
The fourth quarter costs a multiple of the rest of the year, on exactly the stock you hold most of.
days
241 in the UK. US articles say 181, which is a different marketplace and a different currency.
£
Per cubic foot per month, on top of the normal rate, and it climbs steeply at each later tier.
Storage per unit sold

–

Fill in the dimensions to see the answer.

Volume per unit –

Storage a month, per unit, January to September–

Storage a month, per unit, October to December–

Months of cover –

Days to clear the stock –

Storage as a share of contribution –

Share of the shipment aging past the surcharge–

Aged surcharge on this shipment –

Total storage for the whole shipment–

Storage per unit sold is the monthly rate times half your months of cover, because stock running down evenly sits for half its cover on average. Put the monthly rate in your margin instead and you understate slow stock by exactly that multiple.

Free download

Take this estimator into Excel

The workbook adds a table of sales rates, so you can see the point where a slowing product tips past the aged surcharge. It is a cliff rather than a slope: on the worked example, dropping from 75 units a month to 50 takes the share aging past 241 days from nothing to a fifth of the shipment.

Download the Excel workbook XLSX · free · no signup required Not sure what your true contribution per unit is? Get in touch

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