Print Amazon FNSKU labels in a minute
Every unit you send to Fulfillment by Amazon needs a scannable barcode. For most sellers that is the FNSKU label — the Amazon barcode that ties the unit to your seller account. Since Amazon stopped its US prep and item-labeling service on January 1, 2026, you print and stick these labels yourself (or pay a prep center). This FNSKU label generator makes the labels from your FNSKU, title and condition, lays them out on the label sheet or thermal roll you already have, checks them against Amazon’s label rules and gives you a sharp vector PDF.
- Bulk: add products one by one or paste a whole list from Excel, Google Sheets or a CSV file, with the number of labels for each.
- Laser or thermal printer: US Letter 30-up (Avery 5160 size), A4 21, 24, 27 and 40-up sheets, and 2¼″ × 1¼″, 2⅝″ × 1″, 2″ × 1″, 3″ × 1″ and 3″ × 2″ thermal rolls.
- Part-used sheets: start at any label position and nudge the print to line up with your sheet.
- Amazon label check and scan test before you print a whole shipment.
- Private: nothing is uploaded — the PDF is made in your browser.
What is an FNSKU?
The FNSKU (Fulfillment Network Stock Keeping Unit) is the barcode Amazon uses to identify your units in its warehouses. It usually starts with X00 and has 10 characters, for example X001ABC123. When Amazon lets a product be tracked by its manufacturer barcode (usually for brand owners), the FNSKU column shows the ASIN, starting with B0 — then the original UPC or EAN on the packaging is used. If your FNSKU column shows X00…, print that; copying the ASIN by mistake is a common error. You find it in Seller Central under Inventory → Manage FBA inventory (the FNSKU column) or when you create a shipment.
| Code | What it identifies | Looks like | Who gives it |
|---|---|---|---|
| FNSKU | Your units in Amazon’s fulfillment centers | X001ABC123 (or the ASIN) | Amazon, per seller and product |
| ASIN | The product page on Amazon | B0ABC12345 | Amazon, per product |
| UPC / EAN (GTIN) | The product everywhere in retail | 12 or 13 digits | GS1 (the brand owner buys it) |
| SKU | Your own stock code | Anything you choose | You |
You need a UPC or EAN (or a GTIN exemption) to list a new product, and the FNSKU to send it to FBA. Make UPCs with our UPC barcode generator only from numbers you own through GS1.
Amazon FNSKU label requirements
| Rule | Amazon’s requirement | This tool |
|---|---|---|
| Barcode | Code 128, one scannable barcode per unit | Code 128 (set A for FNSKUs), one barcode per label |
| Label size | From 1″ × 2″ up to 2″ × 3″, white label, removable adhesive | Only label sizes inside this range |
| Text | FNSKU under the barcode, product title and condition | FNSKU, title (shortened in the middle if long), condition — the label check warns if one is missing |
| Quiet zone | 0.25″ clear space left and right, 0.125″ above and below | Kept automatically and shown in the label check |
| Bar height | At least 0.25″ | Checked for every size |
| Extra text | Allowed at the bottom, text only — no second barcode | One optional line (e.g. country of origin, expiry) |
| Printer | Laser or thermal printer — Amazon asks sellers not to use inkjet printers | Laser and thermal settings only |
| Durability | Readable and scannable for 24 months, no smudging or fading; removable adhesive | Use laser labels or good-quality thermal labels; removable-adhesive versions exist for the common sizes (e.g. Avery 6460 for the 5160 size) |
Which label size should I use?
| Printer | Best label | Why |
|---|---|---|
| Laser printer (US) | US Letter 30-up, 1″ × 2⅝″ (Avery 5160 size; 6460 is the removable version) | The classic FBA sheet — 30 labels per page, cheap and easy to find |
| Laser printer (UK, EU, Pakistan, India…) | A4 24-up (63.5 × 33.9 mm or 70 × 37 mm) or 21-up | Common A4 sheets with room for a longer title |
| Thermal label printer | 2¼″ × 1¼″ or 2⅝″ × 1″ roll | No ink, fast for big shipments, very durable bars |
| Small products | 2″ × 1″ roll | The smallest size Amazon accepts |
How to print FNSKU labels
- Copy your FNSKUs from Seller Central (Manage FBA inventory), or export them to a spreadsheet.
- Add them above — type them in or paste the list with title, condition and quantity.
- Pick your label sheet or thermal roll and printer type. Fix the start position if part of the sheet is used.
- Look at the preview and the Amazon label check, run the scan test, then download the PDF.
- Print at 100% / Actual size (never “Fit to page”), check one sheet against the labels, then print the rest.
- Scan one printed label with a phone or barcode scanner before labelling the shipment.
Where to put the FNSKU label
- Cover the manufacturer UPC or EAN completely so only one barcode can be scanned — unless the item is approved to use the manufacturer barcode.
- Stick the label flat on the outside of the packaging, away from edges, seams, corners, curves and openings.
- Do not cover the label with tape; clear tape can make it unreadable.
- For sets, label the set (and mark it “Sold as set — do not separate”), not each piece.
- Units in poly bags need the barcode readable through the bag or a label on the outside.
Thermal printer tips
Set the label size in the printer driver to exactly the roll you use (for example 2.25 × 1.25 in), choose 203 or 300 dpi to match the printer in the tool so the bars land on whole printer dots, and print at 100%. If the barcode looks too light, raise the darkness a little rather than enlarging the label. A 4″ × 6″ shipping-label printer can print FNSKU labels too, as long as it has a small-label roll loaded.
Common FNSKU labeling mistakes
- Printing with “Fit to page”. The barcode shrinks and the labels drift off the sheet.
- Wrong FNSKU for the condition. New and used versions of the same product have different FNSKUs.
- Leaving the UPC visible. Two barcodes on one unit can get it scanned as the wrong item.
- Using an inkjet printer. Ink can smudge or blur in the warehouse — Amazon asks for laser or thermal printing.
- Not testing. Always scan one printed label before you label hundreds of units.