I have printed a Code 128 barcode but my scanner doesn't read or scan it

This can have several reasons:
  • Make sure that the code symbology Code 128 is actually activated in the barcode scanner. Consult your scanner's manual.
  • The print quality must be adequate. For Code 128, a resolution of 150-200dpi or higher is recommended. Also, make sure that the code is not printed too small. The minimum module width (i.e. the width of the narrowest bar) should not be below 0.3 mm. The height should not be below 10 mm. A space (the so called "quiet zone") of at least five to ten millimeters should be left around the code.
  • By default, many scanners require a barcode to encode at least four characters. If so, a barcode with only three characters will not scan. Check your barcode scanner's manual.
  • With Code 128 almost all barcode readers on the market today will will expect a checksum with the barcode. If the code does not scan you may have created it without a checksum, a common mistake when using a Code 128 barcode font, see below.

Using a Code 128 barcode font in Excel, Google Sheets

When using a Code 128 barcode font in office applications like Word or Excel, you can't just simply select your numbers and change the font. Instead, you will have to format your data by adding start and stop symbols and a check digit. Usually a macro, add-in, or stand-alone app will be supplied with the font that converts your data for the font and calculates a check digit.

Accordingly, the "Libre" barcode font for Code 128 also requires a separate encoder to create a valid barcode symbol with start/stop characters and check digit; as such it is not practical to use the "Libre" font in Excel. It is also not clear if the font includes the required FNC1 character that is needed to encode Code 128 GS1.

Code 128 sample barcode

Use the following verified sample barcode to test the settings of your scanner. It encodes nine characters, has the required start/stop symbols, the proper checksum, and sufficient quality.

Code 128 - sample barcode to test barcode scanner

Right-click and "Save as..." to print the barcode out. A good CCD scanner or reader app will also be able to scan the code directly from the screen.

For more sample 128 barcodes and a general introduction to Code 128, see our page Code 128 explained.

Verifying Code 128 barcodes

A scanner app is the easiest and fastest way to verify a printed Code 128 barcode. In this video, the free CoScan app for iPhone detects and identifies barcodes on various products:

The app will not only decode the data content but also list the barcode symbology. Similar apps are available for Android.

AppStore (free download)

Creating Code 128 in Adobe Illustrator, InDesign

Use the Softmatic Barcode Extension to generate compliant Code 128 and Code 128 GS1 directly in your Illustrator or InDesign document:

The Softmatic Barcode Extensions for InDesign and Illustrator are available from the Softmatic store.

Creating compliant Code 128 barcodes on Mac / Windows

For the creation of compliant Code 128 symbols like the one above, use Softmatic BarcodePlus V5. This stand-alone app creates all common retail barcodes, like EAN, UPC or ISBN. In addition BarcodePlus V5 supports a wide variety barcodes for warehousing, pharmaceuticals and 2D symbologies like QR, Aztec or PDF417.

This software is very easy to use. Simply select "Code 128", enter your data and the code is created right away. Video shows creation of a 128 GS1 code:

Bulk creation of Code 128

For bulk creation of standards-compliant Code 128 and many other linear and 2D symbologies, see Softmatic BarcodeFactory V5: