Code 39 - Dynamsoft Barcode Reader SDK

What is a Code 39?

As the first alpha-numeric symbol developed in the year 1974 by Intermec, Code 39 is a variable length, discrete barcode symbology. Also, it is often known as Alpha39, Code 3 of 9, Code 3/9, Type 39, USS Code 39, or USD-3.

The name of code 39 comes from the fact that it could only encode 39 characters in total. However, in its most recent version, the character set has been increased to 43. They consist of uppercase letters (A through Z), numeric digits (zero through nine) and a number of special characters (-, ., $, /, +, %, and space). An additional character (denoted ‘*’) is used for both start and stop delimiters. A typical Code 39 barcode appears as such:

Code 39

The barcode itself does not include a check digit. But it is considered self-checking in that a single print defect cannot transpose one character into another valid character.

Code 39 is general purpose and one of the most widely used barcode types. It can be encoded and decoded by almost every barcode encoding/decoding equipment.

There are some drawbacks with Code 39. It has a low data density. It’s also not as compact as, for example, the Code 93 or Code 128 barcodes. That makes it not suitable for very small goods or items which require large amounts of information to be encoded.

Where is a Code 39 used?

Born in 1974, Code 39 is still widely used, especially in non-retail environments. It is supposedly the standard barcode used by the United States Department of Defense and is also used by the Health Industry Bar Code Council (HIBCC).


  • Government
  • Manufacturing
  • Logistics
  • Postal
  • Medical
  • Automotive
  • Defense

How could Dynamsoft help you with Code 39?

Dynamsoft barcode reader enables you to efficiently embed high-speed and reliable barcode reading functionality in your web, desktop or mobile application using just a few lines of code.

Download the free trial SDK, explore our helpful resource center including sample codes, tutorials, guides and more to get started.