Barcodes for a small shop: which type, and how to print them

14 August 2026 · Free QR Pro

If you are labelling stock for your own till, you have more freedom than you think — and one hard rule about colour that catches almost everyone.

Do you need a real GS1 number, or not?

This is the first fork, and it decides everything after it. If your products will be sold through someone else — a supermarket, a distributor, a marketplace that requires it — you need a genuine GS1 prefix, which you buy from GS1 in your country. Nobody can generate that for you, and a made-up number will eventually collide with somebody else's product.

If the labels are only ever scanned by your own till, in your own shop, you do not need GS1 at all. You can use Code 128 with whatever internal reference you already use — SHELF-4471, or a supplier code. This is the case for most small shops, and it saves an annual fee.

What each symbology is actually for

EAN-13 is the retail standard outside North America: 13 digits, the last one calculated from the other twelve. UPC-A is its 12-digit North American cousin — the full decision guide compares all three families side by side. EAN-8 is the short version for small packages where a full EAN-13 will not fit.

Code 128 takes letters as well as numbers and is variable length, which makes it the right choice for internal codes, shelf labels and asset tags. ISBN is a book number that converts into an EAN-13 beginning 978 or 979.

If you are unsure and the code is internal, use Code 128.

The check digit is not optional

The final digit of an EAN or UPC is calculated from the ones before it. A scanner recomputes it on every read and rejects the code if it does not match. That is what stops a smudge being read as a different product.

It also means you cannot invent a barcode number freely. Enter the first twelve digits and let the generator calculate the thirteenth — ours does, and it also verifies the digit if you paste all thirteen, which is how you catch a typo before printing five hundred labels.

The colour rule almost everyone gets wrong

Retail laser scanners read with red light. That is not a detail — it decides which colours work.

In red light, red and orange bars look almost the same brightness as white paper. A red barcode has near-zero contrast to a laser scanner even though it looks perfectly clear to you, and your phone camera will read it happily, which is exactly how the mistake survives testing.

Black on white. If you must use colour, dark blue or dark green on white are the only ones with real margin. Our generator checks the red-channel gap as you type and warns before you print.

Size, and why it is defined in millimetres

Retail barcodes have a nominal size — the standard EAN-13 is about 37 mm wide and 26 mm tall. You may print between 80% and 200% of that. Below 80%, tills start to fail; above 200% you are wasting label.

The trap is scaling. Export a barcode, drop it into a word processor, drag the corner to make it fit, and you have silently left the allowed range. Our generator shows the printed size in millimetres and the percentage of nominal, and the bulk tool does the same for a whole sheet.

Quiet zones, on both sides

A barcode needs blank space either side — for EAN-13 that is about 3 mm on the left and 2 mm on the right. Crop it flush against a coloured label background and it stops scanning, with nothing visibly wrong.

This is the single most common cause of a label that "worked yesterday" after a designer tidied it up.

Doing a whole shelf at once

For more than a handful, put the codes in a spreadsheet with a label and a filename, and generate them together. Our bulk barcode generator validates every check digit before it makes anything, so a bad row is caught at the spreadsheet stage rather than on the printer.

Its print-sheet mode lays them out on A4 at a real millimetre size, with cut marks. That matters more for barcodes than for QR codes, because barcodes have no error correction — a barcode that prints slightly wrong does not degrade, it simply fails.

Test at the till, not at the desk

Print one label, on the paper you will actually use, and scan it with the actual till. Phone cameras are far more forgiving than laser scanners, and a code that reads on your desk can still fail in the shop.

If it fails, the order to check things in is: colour, then quiet zone, then size, then print quality.