Guide to Barcode Symbologies

Codabar Barcode (NW-7)

Example of Codabar

Codabar

 

Codabar is a one-dimensional (1D) linear barcode symbology that was originally developed in the early 1970s. It is a variable-length barcode that can encode numeric data from 0 to 9, along with a small set of special characters: $ : / . +. In addition, Codabar uses four start/stop characters (A, B, C, and D), which are required for scanner recognition but are not normally visible or interpreted as data.

One of Codabar’s defining characteristics is that it is a self-checking barcode, meaning that it does not require a separate checksum character to validate the data. This made Codabar popular in earlier applications where simplicity and ease of printing were more important than high data density or advanced error detection.

Barcode Density and Data Capacity

Although Codabar is considered one of the denser self-checking barcode types, its overall data density is significantly lower when compared to symbologies such as Interleaved 2 of 5 or more modern numeric barcode formats. As a result, Codabar typically requires more physical space to encode the same amount of data.

Codabar does not impose a strict limit on message length, meaning the amount of data stored can vary depending on the application and available label space. However, due to its lower density, Codabar is best suited to short numeric strings rather than long or complex data sets.

Common Uses of Codabar Barcodes

Codabar has traditionally been used in environments where barcode reliability under simple scanning conditions was sufficient. Typical applications include:

  • Blood banks and medical laboratories

  • Library systems (book identification and circulation tracking)

  • Photographic laboratories

  • Air parcel and courier services, including legacy use on FedEx airbills

Its ability to be printed accurately with basic printing technology contributed to its widespread adoption in these sectors during the early years of barcode technology.

Limitations and Modern Usage

While Codabar remains in use in some legacy systems, it is not as versatile or reliable as many modern 1D barcode symbologies. It lacks strong error detection, supports only a limited character set, and offers lower data density than newer alternatives.

For these reasons, Codabar is generally not recommended for new applications or modern logistics, retail, or industrial systems. Organisations implementing new barcode systems are usually better served by more advanced symbologies that offer higher data capacity, improved scanning reliability, and broader industry support.

Summary

Codabar is a simple, numeric barcode symbology with historical significance and continued use in certain legacy environments. However, due to its limitations in density, reliability, and flexibility, it is best reserved for existing systems rather than new barcode implementations.