FNSKU label generator

Why sellers need this

Amazon ended its FBA prep and labelling service in January 2026, and ended commingled inventory that March. Between those two changes, every seller sending stock to Fulfillment by Amazon now applies an FNSKU label to each unit themselves, at whatever volume the business runs at.

An FNSKU is a ten-character alphanumeric code that identifies your specific listing of a product. The label carries it as a Code 128 barcode with the code, the product title and the item condition printed underneath, so receiving staff can scan it or read it.

What this preset does

The tool below starts in barcode mode with the columns a typical FBA export uses: FNSKU, title, condition and quantity. Load a spreadsheet with those headers and the mapping is filled in for you; load anything else and you map it yourself.

The quantity column repeats each row, which is how FBA shipments normally work — twelve units of one SKU means twelve identical labels, not twelve spreadsheet rows.

Barcode quality

On a 5160 laser sheet the symbol is drawn two inches wide inside a label two and five-eighths inches across, leaving five-sixteenths of an inch of quiet zone on each side. Bars are filled vector rectangles rather than an embedded image, so bar edges stay exact at any print resolution.

A ten-character FNSKU that cannot be compressed encodes as 145 modules, which puts the module width just under fourteen thousandths of an inch at that symbol width. FNSKUs containing a run of digits compress into Code 128's numeric mode and come out with fewer, wider bars — which scans more easily, not less.

Thermal stock is also supported at 2.25 by 1.25 inches, one label per page, for Zebra, Rollo and DYMO roll printers.

Before a large run

Print one sheet and scan several labels with the equipment that will actually read them. If scans are unreliable, the calibration sheet prints the same code at four module widths and two bar heights so you can identify your printer's floor rather than guessing at it.