Barcode Generator

How to create a barcode

1. Choose the Barcode type: EAN-13 (retail, 13 digits), UPC-A (retail, 12 digits), Code 128 (text and numbers) or Code 39 (uppercase, digits).
2. Type the Content. For EAN-13, enter 12 digits and the check digit is calculated for you, or enter all 13 digits to have the last one verified. UPC-A works the same way with 11 or 12 digits. Spaces and dashes are ignored for these two types.
3. For Code 39, keep Convert to uppercase automatically ticked so lowercase letters are accepted.
4. Adjust the Bar width, the Height (pixels), the Bar color and the Background color, and choose whether to Show the human-readable text under the bars.
5. The preview updates as you type; Create barcode refreshes it. The Encoded value and the Check digit are shown below it.
6. Pick a PNG size and click Download PNG, or Download SVG for a vector file that stays sharp at any size.

Everything happens in your browser: the values you type are never sent anywhere.

Which barcode type should you use?

• EAN-13 is the standard retail barcode in most of the world (it is also called GTIN-13). It holds exactly 13 digits: a GS1 prefix, a company number, an item number and a check digit.
• UPC-A is the 12-digit retail barcode used in the United States and Canada. A UPC-A code is an EAN-13 with a leading zero, and point-of-sale scanners read both.
• Code 128 encodes all 128 ASCII characters: upper and lower case letters, digits, spaces and punctuation. It is compact and very common for shipping labels, inventory, library cards and internal asset tags. Accented letters such as “é” are not part of ASCII and are refused.
• Code 39 encodes uppercase letters, digits, the space and the symbols - . $ / + %. It produces wider codes than Code 128 but is still required by some industrial, automotive and government systems, and almost every scanner reads it.

For a web address, a paragraph of text or contact details, a QR code is a better choice: it holds far more data and phones read it with their camera app.

How the check digit is calculated

EAN-13 and UPC-A both end with a GS1 modulo-10 check digit that lets the scanner detect a misread. Starting from the rightmost digit before the check digit, the digits are multiplied alternately by 3 and 1. For EAN-13 this means weights 1, 3, 1, 3… from the left; for UPC-A, weights 3, 1, 3, 1… from the left. Add the products, and the check digit is the number you must add to reach the next multiple of 10.

Example with 400638133393: 4×1 + 0×3 + 0×1 + 6×3 + 3×1 + 8×3 + 1×1 + 3×3 + 3×1 + 3×3 + 9×1 + 3×3 = 89. The next multiple of 10 is 90, so the check digit is 1 and the full code is 4006381333931. If you type 13 digits whose last digit is wrong, this tool tells you which digit was expected instead of drawing an invalid code.

Code 128 has its own internal checksum that is added automatically and never printed. Code 39 is drawn without an optional check character.

Printing tips

• Keep the Bar color dark and the Background color light. Red bars, light bars on a dark background and low contrast often fail to scan.
• Leave the white margin around the code (the quiet zone) and do not crop it.
• Use Download SVG for print and packaging, or Print (4×) for a large PNG. Scaling a small PNG up blurs the bars.
• Test a printed sample with the scanner or app that will actually read it.