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EAN-13 Barcode Generator

EAN-13 barcodes with the check digit calculated — and verified if you have one.

Result

PASS

EAN-13 ready to print

Each module prints at 0.319 mm, comfortably inside what a scanner reads. The bars are drawn as vector shapes, so they print at your printer's own resolution rather than being resampled from a bitmap — which is what keeps the module widths exact. Leave the white space either side of the bars clear: a border or a price sticker touching the quiet zone is the most common reason a correctly generated barcode will not scan.

Diagnostic telemetry
Encodes
5901234123457
Symbology
EAN-13
Check digitCalculated, and verified if you supplied one
7
Width in modulesIncluding a 11-module quiet zone each side
117
Printed module widthBelow 0.19 mm, scanners and ordinary printers start to fail
0.319 mm

What this cannot tell you

  • Generated in your browser. The number you encode is never uploaded.
  • Bars are drawn as vector shapes and printed at your printer's own resolution. A barcode saved as a bitmap and scaled on the way to paper is the commonest reason a correctly generated code will not scan.
  • Encodes the number you give it. It cannot tell you whether the number is registered to you — EAN prefixes are allocated by GS1, and a barcode encoding a number allocated to someone else scans perfectly and identifies their product.
  • The nominal EAN-13 size is 37.29 mm wide, and the standard permits 80% to 200% of that. Below 80% the specification stops guaranteeing a read, and the tool says when you are there.

Take this with you

How this test page works

Enter twelve digits and the check digit is calculated; enter thirteen and it is verified rather than trusted. The encoding has a detail that catches generators out: the first digit is never drawn as bars at all. It is carried in the *parity pattern* of the six left-hand digits, which is how a thirteen-digit number fits in the same width as a twelve-digit UPC — and a generator that draws it as a symbol produces a barcode that scans as a different number entirely, invisibly.

What the results mean

Check digit
Calculated with alternating weights of 1 and 3. Supplying a wrong one is rejected here rather than encoded.
The first digit
Encoded in the parity of the left-hand half rather than as bars. This is the part of EAN-13 that most people never notice.
Module width
At the nominal 37.29 mm, a module is 0.33 mm. The standard allows down to 80% of nominal, and below that reads become unreliable.
Quiet zone
Eleven modules on the left and seven on the right. Retail scanners are unforgiving about this.

Common problems and fixes

It says my check digit is wrong
Then the number as printed elsewhere is wrong, or a digit was mistyped. The tool refuses to encode a mismatched check digit because such a barcode cannot be scanned.
The retailer rejected our barcode
Usually the number rather than the printing: retailers require a GS1-allocated prefix, and a made-up or borrowed number is rejected at onboarding.
The barcode is too small on our packaging
Below 80% of the nominal 37.29 mm the standard no longer guarantees a read. If space is that tight, the shorter EAN-8 exists and is allocated separately.

Frequently asked questions

How is the EAN-13 check digit calculated?

Take the first twelve digits, multiply alternate digits by 1 and 3 starting with 1, add the results, and the check digit is whatever brings that total up to the next multiple of ten. Reversing which positions get the 3 produces a plausible wrong answer, which is why this is calculated rather than copied.

Can I make up my own EAN-13 number?

You can encode any thirteen digits, and it will scan. Whether anyone accepts it is a different question: retail barcode numbers are allocated by GS1 in blocks, and a number outside your allocation belongs to someone else's product. For internal use that does not matter; for anything sold in a shop it does.

What size should an EAN-13 barcode be printed?

The nominal size is 37.29 mm wide by 25.93 mm tall, and the standard permits between 80% and 200% of that. At 80% a module is about 0.26 mm, which is around the practical limit for ordinary printing.

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