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BARCODE STUDIO · 11 SYMBOLOGIES · LOCAL

Barcodes that are checked before you print them

Pick the symbology your scanner, shop or warehouse expects. Check digits are calculated for you, and every barcode is read back by a decoder before you download it.

Barcodes
2D codesQR code →
01 · DATA

Data

12 digits, or 13 including the check digit — it is calculated for you.

02 · STYLE

Style

03 · BATCH

Batch

04 · EXPORT

Preview

Barcodes are generated and verified in this tab. Nothing you type is uploaded.

Which barcode should you use?

The right symbology is decided by whoever scans it: a supermarket till, a courier depot, a hospital, your own stockroom. These are the formats this page makes and where each one is expected.

EAN-13

The retail barcode on products almost everywhere outside North America. The number (a GTIN-13) must come from your company prefix licensed by GS1 for shops to accept it.

590123412345

UPC-A

The 12-digit retail barcode used in the United States and Canada. Numbers are licensed through GS1 US; retail scanners there also read EAN-13.

03600029145

EAN-8

A short retail code for packages too small for EAN-13. EAN-8 numbers are assigned individually by GS1 on request.

9638507

UPC-E

A zero-suppressed form of UPC-A for small packs. It only exists for UPC-A numbers with enough zeros to compress.

0123456

Code 128

The default for internal use: inventory, asset tags, shipping labels. Compact, encodes letters and digits, and every scanner reads it. GS1-128 logistics labels are built on it.

SKU-2026-0042

Code 39

An older alphanumeric code still required by some industries and government systems. Wider than Code 128 for the same text, but very tolerant of rough printing.

ASSET-0042

ITF-14

Printed on corrugated outer cartons to identify a case of products (GTIN-14). The heavy bearer bars protect it when printed directly on cardboard.

1540014128876

Codabar

A legacy code still found in libraries, blood banks and older courier systems.

A40156B

Data Matrix

A tiny square code for marking parts, electronics and healthcare packs (GS1 DataMatrix). Holds far more than a linear barcode in a few millimetres.

https://imgc.letvr.com/

PDF417

A stacked code for documents: many driving licences and ID cards, and printed airline boarding passes, which carry the IATA boarding-pass data in it.

ConvertPixel barcode generator · PDF417 sample

Aztec

A square code that needs no quiet zone, used for many rail and airline mobile tickets. It reads well from phone screens.

https://imgc.letvr.com/
RETAIL

Selling in shops? The number matters more than the bars

This page will draw any valid EAN or UPC number, but a retailer or marketplace checks that the number belongs to your company. Retail numbers come from a company prefix licensed by your national GS1 organisation; made-up numbers, or cheap resold ones, can clash with real products and get listings rejected. For your own shelves, warehouse, library or event, none of that applies — use Code 128 with whatever codes you like.

PRINT

Printing barcodes that scan first time

Print dark bars on a light background, and never red bars: most laser and LED scanners light the code with red, so red ink disappears. Keep the quiet zones clear — an EAN-13 needs 11 modules of blank space on the left and 7 on the right — and scale the whole symbol, never only its width. At 100 % an EAN-13 is about 37.3 × 25.9 mm including quiet zones, and GS1 allows 80 % to 200 %. Print at "Actual size" and test with the scanner that will really be used.

Common questions

Do I need to type the check digit?

No. For EAN, UPC and ITF-14 leave it out and it is calculated. If you type it, it is checked, and a wrong digit is reported with the correct one.

Code 128 or Code 39?

Code 128 for anything new: it is shorter for the same text and encodes lower case. Choose Code 39 only when a system or customer specifically asks for it.

Are the files vector?

The SVG is fully vector and can be scaled for any print size. The PDF embeds a 300 dpi image sized for printing, and the PNG is a pixel image at the size you choose.

Should the numbers be printed under the bars?

For retail and logistics codes, yes — people type the number when a label is damaged. Turn it off only when the design has no room and nobody will need to key it in.

Is anything uploaded?

No. Generation and the read-back check both run in this browser tab.

Before you start

Nobody needs a barcode for its own sake. Something downstream will scan it — a shop till, a warehouse system, a courier's sorter, a library desk — and that system decides the symbology, the number format and often the minimum size. Start from what the scanner expects, not from what looks tidy on the label.

What catches people out

Thermal label printers need whole-dot bar widths

A label printer places dots on a fixed grid (a 203 dpi printer has dots about 0.125 mm apart). If the barcode is scaled so a bar falls between dots, the driver rounds some bars wider and others narrower, and the ratio the scanner relies on drifts. Export the SVG and let the label software size it in whole dots, or pick a PNG scale that matches the printer, and test a real label.

Spreadsheets silently drop leading zeros

Many UPC numbers start with 0, and a spreadsheet stores 036000291452 as the number 36000291452. Paste that into a batch and every code is one digit short — or, worse, becomes a different valid number. Format the column as text before typing or pasting product numbers.

One product variant, one number

Retail systems treat the GTIN as the identity of an exact item. A different size, flavour, colour or pack count needs its own number; reusing one across variants makes stock counts and prices collide at the till. Keep a simple register of which number went to which item before you print.

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