Free FNSKU label generator

The first change is the end of commingling. Amazon used to fill an order from the nearest matching unit, whichever seller owned it, and a manufacturer barcode was enough to track that stock. From March 31, 2026, resellers, authorized resellers included, must use Amazon barcodes, and Amazon treats reseller units that arrive without them as defective. Amazon’s barcode choice and labeling FAQ sets out the rules.

The exception is narrow. A brand owner with the Brand Representative selling role in Amazon Brand Registry can skip the sticker for a product that is in new condition and carries a single scannable UPC, EAN or ISBN matching one ASIN. A product with no manufacturer barcode needs an Amazon barcode whoever sells it.

The second change is the end of Amazon’s own labeling. Amazon’s FBA Prep Service page says that from January 1, 2026 it no longer offers prep and item labeling for FBA shipments in the US store, and that shipments created after that date which arrive without proper labeling are not eligible for reimbursement if units are damaged or untraceable. The labels have to be on before the box ships, whether you print them or a prep service does.

An FNSKU is Amazon’s code for your units of a product, as opposed to everyone else’s. Amazon’s barcodes start with an X, and the label carries the code as a Code 128 barcode with the code, the product title and the condition printed as text, so receiving staff can scan it or read it. Print Labels From Excel expects ten letters and digits and, after making the PDF, tells you about any value that does not look like a standard FNSKU; it prints those as given.

Avery 5160, 8160 and 5260 share one layout, and it is the only one here measured on printed stock. A ten-character FNSKU is drawn 2 inches wide with 5/16 inch clear on each side. A value that cannot be compressed encodes as 145 modules, which puts the module width at 13.79 mil. FNSKUs containing a run of digits compress into Code 128’s numeric mode and come out with fewer, wider bars, which scan more easily, not less: X001234567 prints at 17.86 mil. Bars are filled vector rectangles rather than an embedded image, so bar edges stay exact at any print resolution.

Amazon says its seller tools are optimized for thermal printers and that its fulfillment centers use Zebra GX430t printers on a direct thermal setting. For a roll printer, choose Thermal 2 × 1 in or Thermal 2.25 × 1.25 in in step 3. The PDF has one label per page at that size, for Zebra, Rollo and DYMO drivers; thermal labels from Excel covers the driver settings. Neither roll layout has been test-printed yet, so print one label and scan it before a run.

The 2 × 1 roll is tight. To keep the bars at a scannable width, a ten-character FNSKU without digit runs is widened to about 1.76 inches, leaving about 0.12 inch clear at each side. That is the ten-module minimum Code 128 needs, but less than the 0.25 inch Amazon asks for. FNSKUs with long digit runs keep the full 0.25 inch. If you want the full margin on every label, Avery 5160 is the safer choice.

On A4 paper, Amazon lists 21 labels per page at 63.5 × 38.1 mm. That is Avery L7160, which is in the label list under A4 sheets.

Add a spreadsheet with columns named FNSKU, Title, Condition and Quantity and the mapping is filled in for you: FNSKU becomes the barcode and the first line of text under it, Quantity sets the number of copies, and the other columns become the lines after that. Load anything else and choose the columns yourself under More options.

Amazon asks for the FNSKU or ASIN on the label as well as the barcode, which is why the preset prints it as text too. If you rearrange the layout, keep that line.

The quantity column repeats each row, which is how FBA shipments normally work: twelve units of one product means twelve identical labels, not twelve spreadsheet rows. A row with 0 is skipped, and one PDF holds up to 10,000 labels.

A sheet left half used from the last shipment still counts. Open “Printing on a partly used sheet?” in step 3 and pick the first free label on the drawing of the sheet.

Seller Central prints Amazon barcodes from the Label products step when you create a shipment, or from Manage Inventory at any time: straight to a thermal printer, or as a PDF for laser label sheets.

Print Labels From Excel works from rows instead. One file covers every product and its quantity at once, you can start on a part-used sheet, and you can choose any of the 62 sheet and roll layouts. It runs in the browser without signing in to anything, and the file stays on your computer.