Barcode Generator
Create one barcode or validate a batch and place the valid rows on a 30-up US Letter label sheet.
One source list, with every error kept beside its row
Batch mode treats each line as a separate value and keeps the submitted order. A bad check digit, unsupported character, blank row, or optionally flagged duplicate stays attached to that line as an error. Valid rows continue into the label preview, so one mistake does not hide the rest of the batch.
Code 128, EAN-13, and UPC-A have different jobs
Code 128 on this page encodes printable ASCII and is useful for internal values such as asset or inventory labels. It is ordinary Code 128-B. GS1-128 has additional FNC1 and Application Identifier requirements that this page does not implement.
EAN-13 and UPC-A encode numeric identifiers with a final Mod-10 check digit. Enter a body without that final digit to calculate it, or enter a complete value to validate it. Leading zeroes are preserved because the engine handles identifiers as text.
For a web address or longer text that a phone camera should open, make a QR code instead.
A barcode image does not create identifier authority
Rendering an EAN-13 or UPC-A pattern does not assign a GTIN or establish ownership. ToolNeko does not issue, sell, register, authorize, or look up identifiers. When a retailer, marketplace, or supply chain requires an authorized GTIN, follow that organization’s rules and the applicable GS1 process.
The 30-up layout is a starting point for a real print test
The print stylesheet uses US Letter paper with three columns, ten rows, 2.625 × 1 inch labels, 0.1875 inch side margins, 0.5 inch top and bottom margins, and 0.125 inch horizontal gaps. Browser, printer, stock, scaling, toner, ink, and surface conditions can change the physical result. Print at 100% with headers and footers off, then scan a representative sheet before using a larger batch.
Local processing and fixed analytics
Generation, validation, SVG rendering, PNG rasterization, and sheet layout happen in the current browser tab. Values are not written to the URL or browser storage. Measurement events use fixed mode and action names rather than the text, digits, captions, or filenames you submit.
Frequently asked questions
Which barcode type should I choose?
Use Code 128 for compact printable ASCII such as an internal item or asset code. Use EAN-13 or UPC-A only when you already have the corresponding numeric identifier. Ordinary Code 128 on this page is not GS1-128.
Can I generate several barcodes at once?
Yes. Choose Batch + labels and paste one value per line. The tool validates up to 30 rows, keeps their order, identifies each invalid row, and places valid results on a 30-up US Letter sheet.
Does ToolNeko give me an official GTIN, UPC, or EAN?
No. The page draws values you supply and can calculate or validate the final check digit. It does not issue, register, sell, authorize, or look up identifiers. Contact GS1 when you need an authorized GTIN.
Why did the EAN-13 or UPC-A value change in the result?
A 12-digit EAN-13 body or 11-digit UPC-A body is completed with its calculated check digit. A complete 13- or 12-digit value is validated instead. The original field is never silently rewritten.
Will every printed label scan?
Barcode reading depends on printer resolution, scaling, contrast, label stock, surface, scanner, and required quiet zones. The sheet is a browser print layout, so test a representative sheet in the exact workflow before relying on it.